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MG TD TF 1500 - New oils bad for our cars...

Hi All,

Check out this email I received recently from an mg specialist & racer.




By: Keith Ansell, Foreign Parts Positively, Inc.

About a year ago I read about the reduction of zinc dithiophosphate (ZDDP) in the oils supplied with API approval that could affect sliding and high pressure (EP) friction in our cars. The reduction of these chemicals in supplied oil was based on the fact that zinc, manganese and/or phosphates reduce the effectiveness and eventually damage catalytic converters and introduce minute amounts of pollutants into our atmosphere.

A month or so ago I had a member of the Columbia Gorge MG Club bring a totally failed camshaft and lifters back to me that had only 900 miles on them!! I immediately contacted the camshaft re-grinder and asked how this could happen. They were well aware of this problem as they were starting to have many failures of this type. In the past, the lack of a molybdenum disulfide camshaft assembly lubricant, at assembly, was about the only thing that could create this type of problem. My customer has assembled many engines and had lubricated the camshaft properly and followed correct break in procedures.

This got me on the phone to Delta Camshaft, one of our major suppliers. Then the bad news came out: Its todays modern API (American Petroleum Industry) approved oils that are killing our engines.

Next call: To another major camshaft supplier, both stock and performance (Crane). They now have an additive for whatever oil you are using during break-in so that the camshaft and lifters wont fail in an unreasonably short period of time. They also suggest using a diesel rated oil on flat tappet engines.

Next call: To a racing oil manufacturer that we use for the race cars (Redline). Their response: We are well aware of the problem and we still use the correct amounts of those additives in our products. They continued to tell me they are not producing API approved oils so they dont have to test and comply. Their oils were NOT the new, improved and approved ones that destroy flat tappet engines! We just build the best lubricants possible. Sounds stupid, doesnt it, New-Approved but inferior products, but it seems to be true for our cars.

To top this off: Our representative from a major supplier of performance and street engine parts (EPWI) stopped by to warn us of the problem of the NEW oils on flat tappet engines. This was a call that the representative was making only because of this problem to warn their engine builders! The reduction of the zinc, manganese and phosphates are causing very early destruction of cams and followers. They are recommending that, for now at least, there must be a proper oil additive put in the first oil used on new engines, beyond the liberal use of molydisulfide assembly lube. They have been told that the first oil is the time the additives are needed but remain skeptical that the first change is all that is necessary. Their statement: Use diesel rated oils such as Delo or Rotella that are usually available at auto stores and gas stations.

This problem is BIG! American Engine Rebuilder's Association (AERA) Bulletin #TB2333 directly addresses this problem. I had a short discussion with their engineer and he agreed with all that I had been finding.

Next phone call was to a retired engineer from Clevite, a major bearing and component manufacturer. First surprise was that he restored older British Motor bikes. The second surprise was that he was VERY aware of this problem because many of the old bikes had rectangular tappets that couldnt rotate and are having a very large problem with the new oils. He has written an article for the British Bike community that verify all the bad news we have been finding.

Comp Cams put out #225 Tech Bulletin: Flat Tappet Camshafts. They have both an assembly lube and an oil additive. The telling sentence in the bulletin was While this additive was originally developed specifically for break-in protection, subsequent testing has proven the durability benefits of its long term use. This special blend of additives promotes proper break-in and protects against premature cam and lifter failure by replacing some of the beneficial ingredients that the oil companies have been required to remove from the off theshelf oil.

Next question: Now what do we do?

From the camshaft re-grinders (DeltaCam) Use oils rated for diesel use, Delo (Standard Oil product) was named. About the same price as other quality petroleum based oils. They are not API formulated and have the zinc dithiophosphate we need in weights we are familiar with.

From the camshaft manufacturer (Crane): use our additive for at least the first 500 miles.

From General Motors (Chevrolet): add EOS, their oil fortifier, to your oil, its only about $12.00 for each oil change for an 8 ounce can (This problem seems to be something GM has known about for some time!).

From Redline Oil: Use our street formulated synthetics. They have what we need!

From our major oil distributor: Distributing Castro, Redline, Valvoline and Industrial oils: After over a week of contacts we have verified that the major oil companies are aware of the problem. The representatives of the oil companies today are only aware of marketing programs and have no knowledge of formulation. The only major oil companies they were aware of for doing anything to address this are Valvoline that is offering an Off Road 20W-50 and Redline.

From Castrol: We are beginning to see a pattern emerging on older cars. It may be advantageous to use a non-approved lubricant, such as oils that are Diesel rated, 4 Cycle Motorcycle oils and other specified diesel oils.

Last question: So what are we at Foreign Parts Positively going to do? After much research we are switching to Redline Street rated oils and stocking the Castrol products that are diesel rated. Castrol, owned by British Petroleum, is now just a brand name. This is a difficult decision as we have been a dealer and great believer in all Castrol Products for over 40 years. We have been using Castrol Syntech oil in new engines for about 3 years so the cost difference in changing to Redline is minimal. The actual cost in operation is also less as the additive package in Redline makes a 1-year or up to 18,000 mile change recommended! Yes, it is a long change interval but with lowered sulfur levels and the elimination of lead and many other chemicals in the fuels there are less contaminants in our oil from the fuel, which is the major contributor to oil degradation. We will continue to offer the Castrol products but will now only stock the suggested diesel oils that they produce.

Too many things are starting to show up on this subject and it has cost us money and time. Be aware that New and Improved, or even products we have been using for many years, are destroying our cars as it isnt the same stuff we were getting even a year ago.

For the cars that use engine oil in their gearboxes this may even pose a problem as these additives that have been removed could be very critical in gear wear. We will be using oil specifically formulated for Manual Gearboxes with Brass Synchronizers. The only oils we are aware of that fit the criteria are from General Motors and Redline.

If you have any additional input let us know. We need to let every flat tappet engine owner, i.e.: every British Car owner know that things are changing and we MUST meet the challenge.

Keith Ansell, President

Foreign Parts Positively, Inc.



Use multi grade 20/50....
gblawson - TD#27667

I'll stick with 20/50 as I have for nearly 20 years in my MGs, but this has me thinking about changing brands!
Steve Simmons

This should be an issue for all the oil companies who have special "Classic" product ranges. If ever there will be an USP for them, this is it !
Remo Peter

I use the 20/50 but now use the " not steet legal" Valvoline racing oil instead of the 20/50 Castrol GTX I've been using for 30 years. It's supposed to have the zinc we're looking for. A recommended alternative was to head to the Harley shop and pay the big bucks for the motorcycle oil. Still using Castrol Syntec in the modern mobiles ( probably made by Ashland oil also). I suspect that the diesil oils will be changing soon as they have new emission regulations going into affect January 1, 2007. Local GMC dealer said that after 1/1/07 diesil trucks will go up $3000.00 USD to cover the cost of the added emission equipment.


Bob Wagner at Atlanta Imported Auto Parts is a noted engine rebuilder for vintage race cars. At our Tech Session last January, he discussed the rebuilding and dyno tuning of my XPEG engine. He told us that the vintage racers with pushrod engines and hard tappets had been experienceing severe camshaft failures in a short time after engine rebuilding due to the removal of the zinc from most of the oils. Those that switched to diesel type oils (Shell Rotella T) or Redline were not experiencing such failures..............

All the standard 20W50 passenger car oils have been reformulated without the zinc (Castrol 20W50 for example). ( A warning to Lawson and Simmons above, yes we have used the products for years with no problems, but they have now changed.)
It just takes a bit longer on an engine that was using the old formulation and redcently change to the new API oil, than on a rebuilt engine christened on the new oil.

Don H
Don Harmer

I think it would be a service if someone very knowledgeable on this subject would post a list of known brands and "specific" products that MEET the criteria we are looking for. So far all I can come up with from this thread to use is Redline. Thanks to anyone that will.

L Karpman

Isn't Redline synthetic?
Robert Dougherty

Very interesting. Remember a while ago the Moss/Crane cam tappet failures? Maybe not the parts fault? Anyone know how the new Moss hardened/tested tappets are holding up? George
George Butz

Just came from the Castrol web site, they list GTX 20-50 with 0 zinc, Syntec blend with 0 zinc. GTX 20-50 diesel has .13 zinc content....there seems to be something to this...
Robert Dougherty


The only Zinc (ZDDP/ZDP) free oil I am aware of is Fuch Titan GT1 0W20

Uprated cams may require more ZDDP and look to race Bike Diesel oil, but in general the following should apply from the Penrite site

An engine oil that contains about 0.1% phosphorus or higher, will easily provide the required anti wear properties for older engines.

The step from API SH to API SL was accomplished by a combination of new additives or adding additional anti wear and anti oxidant to existing blends. These were not phosphorus based, but used organic molybdenum additives (not molybdenum disulphide - aftermarket oil additive), to keep phosphorus levels at 0.1%.

Now we have API SM – for the first time, the limit on phosphorus is from 0.06-0.08%. There are industry concerns about the applicability of these oils in older engines. However, the limit only applies to 0W-20, 0W-30, 5W-20, 5W-30 and 10W-30 oils (so called “ILSAC” grades). Any other grades are exempt from this.

Therefore even blanket statements about API SM oils will be incorrect and further research will be needed by the end user.

There is one other factor with non-ILSAC oil grades. If they also have the European ACEA A2/A3 with B2/B3 or B4 performance levels, phosphorus levels will also be at 0.10 % to 0.12% as their tests have been more severe than the API for some time. Hence an oil that is SL (SM)/CF/A3/B3 also well exceeds the anti-wear requirements for older engines.

The irony is that API SF and SG oils formulated in recent years usually have phosphorus contents of around 0.08% (usually 0.1% maximum) anyway due to other advances in technology, unless the blender chooses to add extra additive.

ZDDP is compared for Bike oils

Paul Wiley

This article may also be of interest
Paul Wiley

Hmmm...based on all the above comments including the HOT ROD article, I should seriously consider Redline synthetic oil for my next oil change!

Anyone agree/disagree with this? Perspiring minds need to know.... <grin>


dave lackey

hello, "old cars weekly" just reprinted an article from "skinned knuckles" magazine. the article mentioned the diesel oils and the redline products, but stated there is no supporting test data or verified field evidence to support what appears to be, at this point, folklore. last weeks "old cars weekly" or the back issue of "skinned knuckles" can be referenced. regards, tom
tm peterson

The issue with thin oils and low ZDDP is you are that bit closer to edge. The cam break in tends to be solved by high zinc with 3% being used to ensure uptake. In these circumstance high ester based oils Redline etc may actually compete for surface with ZDDP and moly. Post break in then the low ZDDP may be sufficient but higher ZDDP is not a problem. Additives do not lubricate so Diesel oils may not be best choice because of robust add pack. Redline is perhaps the highest off the shelf ester based oil with high ZDDP and moly but its not cheap.

The current crop of thin oils, because they need to use a more refined base oil, are "drier" as is PAO, and esters are being used which may account for the good wear obtained with low ZDDP.
Paul Wiley

I have forwarded Keith Ansell's text to Penrite Switzerland. Already got reply - they are very concerned (and surprised?) and will take the matter to their headquarters.
Remo Peter

Hi all

For those in the UK, I contacted Millers Oils about this issue and this is the reply I got:

"Reduction in Zinc levels applies to engines meeting Euro IV emissions onwards with Catalytic convertors, Particulate traps etc. This type of exhaust after treatment often needs chemical limitations hence the lowering of Zinc levels which acts as an anti wear agent.
The technology for older engines still exists however. See the attached info for Millers Classic 20w/50 which is a traditional zinc rich formulation for older engines."

So Millers are well aware of the standards and their Classic 20W/50 looks a safe bet to use.

Millers Oils:


David Wardell

As others have mentioned, this is a NEW problem because the oils we have relied on in the past have changed their formulations. So good old Castrol 20W50 won't work anymore, and as mentioned the oil you bought last year is probably different than the oil you would buy this year (same brand).

I have heard numerous recommendations for Redline on various car message boards, both for older and modern cars. I will probably be switching to that, unless I can find something like Castrol diesel grade oils locally, or Valvoline off-road 20W50 locally.


I have a hard time believing that there is only one product - Redline - that would meet this new need mentioned with regard to camshafts. I heard of this via Atlanta Imports (just like Don Harmer) and have been looking into it as well. In looking over the above responses, I cant see any agreement - some say that there IS a problem - others claim that there ISN'T. I think we should first try to confirm the problem - them jump forward to discussing the solution - if on is needed.

Is the probem just with the camshafts? If so - what is the evidence of the problem - evidence in non racing cars would be of interest?

I did hear that Don's camshaft was in bad shape and this prompted some of Bob's remarks at the Atlanta Imported Auto session.

Have any other owners had camshaft problems? If so how many and what were the various conditions underwhich the problems came to be noticed?

I am running the Rotella as a result of Bob's suggestion - but I'd like to know what the real frequency of failure has been.

Are we all running around like chicken little? What are the broad-based facts?

Good thread topic!

J Delk

Actually, the original message gave a number of options besides Redline: Valvoline off-road, diesel-rated oils, 4-cycle motorcycle oils, Delo, etc.

My purpose in posting this is that with all of the research the original writer put in to his article, ACTUALLY CALLING AND TALKING with parts suppliers and oil companies, this is a KNOWN problem. People aren't just making guesses on these things.

In addition, this is being seen in road-going cars as well as racing cars.

The research by Keith, plus the number of articles being written about this issue, plus the reports from other independent shops regarding camshaft failures easily convinces me to change from the oil I've been using for 31 years (Castrol 20W50) to something else. I've exchanged emails with Keith and met him once, and he is not the type to change the oil he uses in his shop without VERY good reasons...


Thanks Scott - I feel safe with Rotella - I guess - it just seems strange that the major suppliers wouldnt address this or atleast comment on it in an open way - or have a special oil that they would charge us more to purchase - in other words a Castrol for vintage use.. hope they dont see this

J Delk

I prefer ZDDP and Moly


Calcium 2884
Magnesium 10
Phosphorus 1164
Zinc 1311

Mobile 1 R
Calcium 3024
Magnesium 13
Phosphorus 1399
Zinc 1536
Moly 78

Calcium 4015
Phosphorus 1790
Zinc 2014
Molybdenum 961

Paul Wiley

The Penrite Classic oil contains the following additives,
Magnesium 0.102%
Zinc 0.099%
Phosphorus 0.090%
Sulphated Ash 0.55%
I don't know if Penrite is available in the US but it is in UK.
R.w. Styles

I was looking for one of the above mentioned additives to use with the castrol 20-50 now in my car, and couldn't find them. I did find that good old STP has zinc (ZDDP) in it though, and remembered that my old British car mechanic in the 60's swore by the stuff. So I got some and put it in.

Today, I noticed quite an improvement. The engine was quieter on startup (that 2-3 seconds when the valve train is noisy until the oil pressure is up), and seems much quieter overall. The STP bottle specifically mentions cushioning hard metal parts.

I plan to switch to redline non racing 10-40 oil, next oil change. You should read about the oils on their site before selecting one. They are very specific about the applicability of the various oils.

Larry Ayres

Castrol does sell a "Classic" range of oils. On their Swiss website no contact e-mail address is given, only a contact form that does not accept texts over 500 characters long. So no chance submitting Keith's text to them.
Does anyone here know the "Multimiles" oil brand ? They claim to be a "biosynthetic" oil with much better antiwear properties than HD oil even before putting metal-based additives in. They are a Swiss trader, but I heard they use USA-made base products.
Remo Peter

I sent Pennzoil a copy of the article and the question of which of their brands might work for us... still no response after 48 hours.
I stopped using Castrol 20/50 when I pulled the valve cover (cold) and found a bunch of sludge in all the corners...gave me heart failure. Am told Castro 'does' sure it doens't hurt...just didn't like it).
gblawson - TD#27667

scott, in addition to the august 2006 "skinned knuckles" i will also refer you to the october 2006 "skinned knuckles". from page 5 second column, 3rd paragraph and i quote, "Is the lack of zinc and phosphorous as big a problem as it appears to be? NO! emphatically, no. So many of the on-line chat rooms are talking about the new oils being harmful or even dangerous to our older engines. Look at the source. everyone "knows someone, who knows someone" whose engine was supposedly destroyed by modern oils. I question that. If all of these new URBAN LEGENDS were true, there would be a mountain of destroyed engines to rival mount everest. It only takes one person to yell "fire" with conviction and the entire theater empties out.well, someone yelled 'fire" about engine oils and started a stampede for the exit.." The author of the article went to several sources for th e story. one of which is the American Petroleum Institute, whose testing criteria is so stringent the military dropped the need for mil specs on oilo in the 1970's. the article also states that 2 of the many testing requirements that oil has to meet deal SPECIFICALLY with tappet/cam wear. ALL modern oils that meet the API testing criteria are suitalble for "ALL ENGINES CURRENTLY IN SERVICE" !!! all that is info from the skinned knuckles article, my own feelings are what was in the oils they used in the '50's??? there have been so many advances in petroleum chemistry in the last 60 years. laboratory tested wear additives have been added to replace the zinc and phosphorous. i would be interested in reading other CERTIFIED test results. regards, tom
tm peterson

I work as an engineer and am not prone to rash decisions (at least regarding my MG). The problem seems to be documented from what I would call reliable sources, although I will acknowledge that there was a similar false alarm after lead was removed from gasoline regarding excessive valve wear.

I have also heard, on this BBS of people getting "bad" crane cams from a major supplier, that could in fact have been caused by oil problems. Also, we must realize that most people driving older cars don't drive them that much, so it might take years for a "mountain of destroyed engines" to accumulate. I am not prepared to wait for mine to have to be thrown on the scrap heap, when simply an additive or brand switch of oil may not only prevent the problem but have other benefits related to engine wear, as well.

Let's face it, the oil industry may not have done extensive testing with older engines. "Science" or should I say for profit corporations have made mistakes before: DDT, Lead in Gas, MTBE, etc.

Finally, I do trust my own ears. After adding an additive with zink/ZDDP to my oil, the valve train is discernably quieter that with non-zinc oil.


Larry Ayres

Until we hear from various companies/2nd opinions/testers, is there something I can go down to an autoparts store and add to the Pennzoil 20/50 I'm using?
gblawson - TD#27667

I used STP, but others above mentioned a Valvoline and GM EOS product. Look for zinc or ZDDP (an abbreviation for some long chemical that starts with zinc) in it.

Larry Ayres


The article that I posted at the start of this thread lists various industry people that the engine rebuilder contacted, from cam manufacturers, cam regrinders, oil producers, and others in the engine rebuilding business.

The Skinned Knuckles article you quote gives NO supporting information, no actual measurements to validate that removing these additives isn't detrimental to older engines (which were specifically added in the first place to address issues with cams, etc.).

If there is data behind the rest of that article, then I'd be happy to read it and evaluate it based on its references, studies and analysis. Just making a simple statement "it ain't so" flies in the face of what the cam people and even the oil producers seem to be saying...

Scott Linn

Easy to check. I have delt with Delta for cams before. I have sent them an e-mail to confirm if this is their findings.
Bruce Cunha

SM oils need to pass the Sequence IIIG test using a pushrod pig-iron engine equipped with flat tappets of circa 1986 configuration. This was intentionally done to eliminate all concerns with valvetrain wear in older engines. Even the Japanese manufacturers who initially raised the concern agreed with the conclusion.
Paul Wiley

These are the change in oil specs

SG - Introduced 1989 has much more active dispersant to combat black sludge.

SH - Introduced 1993 has same engine tests as SG, but includes phosphorus limit 0.12%, together with control of foam, volatility and shear stability.

SJ - Introduced 1996 has the same engine tests as SG/SH, but phosphorus limit 0.10% together with variation on volatility limits

SL - Introduced 2001, all new engine tests reflective of modern engine designs meeting current emmissions standards

On the basis that SM oils are not related yet to any failures as only apply to low viscosity. Any failures should show up when the lower level was adopted. It would be useful if supporting information can be provided.
Paul Wiley

scott, the article is researched and footnoted. the portion i quoted is only one small paragraph out of a series of multipage aricles. part 1 august 2006, part 2 is october 2006 part 3 will appear in the november issue. my copy of skinned knuckles does give credit to the sources. if your copy is missing these the folks at skinned knuckles will send you a fresh copy. for me, the API standards and tests are good enough. i will reread the article above but the only oil mfg. i see quoted is redline. the redline person quoted says they don't submit their oil for independant lab testing to determine compliance with industry standard performance. hmmm.... hey, if using diesel oil or dumping an additive in makes you sleep better at night, by all it. this hobby is about enjoying the old cars. "drive 'em if you got 'em. regards, tom p.s. paul thank you for the link. regards, tp
tm peterson

I was perusing one of my older Moss TD catalogs tonight, and found the following:

"Most current oils have severely reduced this zinc content leading to elevated stresses where rubbing occurs and therefore potential premature cam lobe and lifter failure".

From Amsoil:
"Third, the oil's ZDDP (zinc dialkyldithiophosphate) additive is very important in protecting heavily loaded, boundary-lubricated parts, such as cam lobes, valve lifters, piston rings and cylinder bores. Boundary lubrication results when metal-to-metal contact occurs, "which in turn causes the deposition of the antiwear film from ZDDP."

While the antiwear properties of ZDDP will not completely eliminate wear, "they will reduce wear by orders of magnitude so that it will not likely be a limiting factor on engine life," Bergin said.

So we have at least the following manufacturers/suppliers being apparently fooled by this so-called "urban legend":

Crane cams
Delta cams
Comp Cams
EPWI engine part supplier
Redline oils
Castrol oils
Spectro oils
American Engine Rebuilder's Association
General Motors
Moss Motors
Hot Rod Magazine
Power and Performance News
Hughes Engines
Motorcycle Cruiser
and probably a huge list from here

One would think that before an oil company would state that their oils wouldn't work well in older cars, that they would have a darn good reason to not recommend their use anymore, especially when their particular oils are in the recommended list supplied in the car handbooks... It would be the easiest thing to dismiss all this as "urban legend", yet they aren't.

I would like to see the references listed in the Busted Knuckles article. I did a web search to try and find articles that listed the camshaft failure issue as not a problem or an urban legend, and I didn't find anything. But there were certainly lots of pages attesting to a problem, with many quotes from oil manufacturers, etc.

See also:

This is an interesting site which analyzes "virgin" oil:


Well, the thread has now become 'he said', 'they said'...!
Do we add oil with Zinc D........, use modern oil, use synth oil, or use an additive...?
Does a tappet made of 1950's steel require more of anything then a tappet made out of 2006 steel... seems to me the rubbing/moving part is still the same? (or is everything hydraulic/rollers now days and doesn't count?)

I switched to Mobil 1 in a 5 series and found it used way more then 'dino' oil and switched back...haven't used synth since...leakage was a factor as well.... Would rather not go that route with the TD...

Pennzoil haven't written back with even a 'form letter' assuring me of the safe use of their oil, or giving me an alternative... would think they wouldn't ignore a problem/urban legend/rumour like this?

Anyway... will put the car away soon and wait with interest for more findings/postings/denials/confirmations....

Am starting to lose track of which the urban legend is... more wear in old engines with modern oils, or 'no' more wear in old engines with modern oils?
gblawson - TD#27667

This problem is not all urbane legend, although the contributing causes get a little murky. The company I was with had a fleet of light trucks which suddenly started having engine problems in the late 90s. These were late model low mileage (20,000 range) Chevrolet pickups which were used by supervisors, mainly commuting on the highway. The failure were camshafts, from high lobe wear. Of course GM blamed the oil, the Oil Company blamed the camshaft material, the camshaft supplier said that GM was operating the cam at a bad rpm in that engine ?, etc. Another contributing fact, was the recent changes on the API specs. This being the most recent change, led most of the in house engineers to think it was the main cause.
We had some of the camshafts tested for hardness, but testing results were also murky, due to the effects of the failure. New shafts that were tested were within spec. Anyway, we changed oil specs and started using an additive. The problem went away but as GM was involved with the cams also, it it hard to say exactly what the root problem was. Maybe a combination of modern manufacturing shortcuts in both metallurgy and oil production- translated as Cost Saving.

I use an oil additive, mostly for upper cylinder lube, but it has some added benefit for high wear areas such as the cam.
Dallas Congleton

"I use an oil additive, mostly for upper cylinder lube, but it has some added benefit for high wear areas such as the cam."

We are listening...
Carl Floyd

Carl, any of the additives with zinc dialkyldithiophosphate (Zinc-d) will address the cam wear problem. Zinc-d is found in Mechanics Brand Engine Tune Up, K Mart Super Oil Treatment, and STP Engine Treatment With XEP2, among others. It used to be in all the oils, but this thread has addresses its removal to protect catalytic converters.
What hasn't been said is what the engine manufacturers have done(if anything) to retain wear characteristics of the cam lobes and lifters.
It is another debate as to whether upper cylinder lube will also help eliminate cam wear-unless it also has an additive such as zinc-d or TCP (Tri-Cresyl-Phosphate). I should have said I also use this additive in the oil sump also.
Dallas Congleton

Pennzoil/Shell reply:

They/he managed to side step the 'older' engines...

Thank you for your inquiry.

Pennzoil has marketed, for a number of years, a "Pennzoil Racing Motor Oil" that would be suitable to use in older vehicles or high performance engines that incorporate high lift cams with high tension valve springs. The Pennzoil Racing Motor Oil is available in the SAE 25W-50, 50, and 60 weight. The product part number is 3623, 3589, and 3599 respectively. Given the part number, any retail outlet that carries Pennzoil products, can obtain this oil. This formulation contains nearly three times as much zinc as most commercially available API "SM" motor oils in the market. I would recommend using this formulation, for truly high performance engines, over the heavy -duty diesel engine oils because this oil has approximately 50% more zinc than most API "CI-4" quality diesel engine oils.

Best Regards,
Technical Service
gblawson - TD#27667

Hey GB - I think he uses the term "older vehicles" ae meaning "older engines."

If those oils have 50% moire zinc - sounds like that might be helpful.. Maybe we need a summary chart of the various oils and a breakdown of the various component additives for good comparison - similar to what we provided earlier.

You wouod think every auto enthusiast publication on the planet would be all over this topic.

Currently using the Rotella - now thinking I should change to the Pennzoil 25w50 mentioned above.

J Delk

scott, the publication is "skinned knuckles, a journal of car restoration". (they have been around for 30+ years.) i am like you..i just love old cars. i am also, like you, just passing information that have along to fellow posters. neither skinned knuckles nor myself have any vested interest in anything other than passing info to car lovers. i am comfortable running modern oils in my motors. if you are not, but addng an additive helps you sleep better at night, do it. drive 'em if you got 'em. regards, tom
tm peterson

Was in Auto Zone store today. I don't believe they are known for top notch technical experts :-) However, while I had grabbed the hose that I needed, I wandered over to the Oil Additive section to read some labels for ZDDP. A young man walked over (probably early twenties) and asked if he could help. I was hesintant to say yes, because that usually just leads to a fruitless conversation, but he saw me intently looking at the letters ZDDP on the front of the STP Oil Treatment bottle. He said, "Looking for that zinc, eh?" "Must have an old classic." I was, to say the least surprised. He seemed to know all about the contraversy, and mentioned Pennzoil Racing Motor Oil 25/50, Redline, and Rottla. Once again I was surprised.

Doesn't add anything to the thread I suppose. I just can't seem to recover from the shock of someone at Auto Zone knowing too much :-)

L Karpman

Just changed the oil in my TD & MGB with Valvoline Racing 20W50...states right on the container that it contains ZDDP...$3.69 at NAPA & Schucks Auto.
Robert Dougherty

This site might be a good start for those - like me - who didn't earn a college degree in technology. This provides some good information on the various aspects of what we are all talking about. I am sure there are other good sites as well.

These is also a similar discussion going on in the MGB technical section of the website.

Best regards,

J Delk

I just bought some Mobil "Drive Clean" 20W-50 and according to the MSDS report this oil has the zinc additive in it. less than 2.5%
As for the price, our local Murray's Auto Parts had it for $1.29 a quart...what a deal and zinc too. I went back and bought the last 3 cases they had.

If you check any of the oil companies web sites you can find the MSDS and product information which will tell you which oils still contain "zinc".
Castrol GTX does not appear to have any in it. However the GTX Diesel version has .13%, but only comes in 10W-40 blend. Interesting note, on the GTX Diesel web page, shows a couple of erstwhile oil changers filling a E-Type Jag......that OHC is not diesel I know of.
Colin Stafford

What roles do calcium and phosporus play in this blend - we have talked a bit about zinc...sorry to be behind the curve on this
J Delk

Zinc see post on MGB

Moly and Boron are also used.
Paul Wiley

Have you used this oil extreme concentrate ? The claims of increasing horsepower (5-7) with their oil would be welcome in a MGTD !

Also would be interested if anyone has used it for a long time and not had any problems with it.

Larry Ayres

Hmmm...I'm always leary when I read something like:

"Oil Extreme's™ brilliant chemist has developed a revolutionary new way of manipulating the molecules of calcium carbonate so he could "overbase", or add excess amounts to the Oil Extreme™ additive package booster. Under heat and pressure this excess calcium carbonate forms an extremely hard tribochemical film that fills the asperities of an engine's metal surfaces."
Considering Calcium Carbonite is basically 'stone'...I'm not sure?... There again, the scientist is 'brilliant'..... to go out... now where is that coloured hair spray I bought!!!
gblawson - TD#27667


Some time ago I believe David Vizard recommended it, but no longer a link to DV.

Aftermarket additives are likely to upset the chemical balance of a properly formulated oil.

"Overbased" Ca is available and may be used in oils for anti wear as well as usual function. A GII base oil is not the quality of esters/PAO/GIII

Safety Fast - I'm expecting 15% Primary and 85% secondary on the ZDDP question.
Paul Wiley

I just went to Advance Auto Parts and picked up six quarts of Valvoline "VR1" Racing Oil 20W-50, part #VV211, at $3.48/qt. It states on the back of the bottle: "Ashless anti-wear additives and ZDDP provide ultimate wear protection." It seems to me like this is acceptable stuff, given the discussion so far.

Here is Valvoline's web page on this product:

This has been truly an interesting topic and I wouldn't have known about it otherwise if not for this BBS!

B Sieling


Confirmation that this oil contains a healthy ZDDP content
Paul Wiley

Just my two cents worth.

Racing Oil is not intended to be used in street engines where it will used for extended time or mileage It has always been my understanding that racing oils lack the detergents that are in regular automobile engine oil. They are formulated to function at very high temps and under extreme conditions for a very short period of time. In my younger days we would change oil at the end of each thirty minutes of track time or after each race, so build up and sludge was never a consideration. In a street car, especially one that is run under very mild conditions and then put up for several days or even weeks with the old oil still in the engine I think that I would stay away from “Racing Oils”


T. L. Manion Thomas

Difference between Racing Oils that are labled "for off road use only" & API approved Racing oils. Point taken about non API rated racing oil...Valvoline VR1 Racing oil is fully API rated...
Robert Dougherty

RL is about the only race (lack of detergent oil) I can think of, may be others and certainly in general "race" oils probably should not be used for modern extended drain intervals, although a long way back now, Calcium is higher in RL road and M1 race than Rotella.

With old generation mineral oils the oils themselves could not stand the extremes and then there was Castor oil (early ester oil).

ZDDP is multi function - anti wear, anti oxidant and inhibits corrosion.
Paul Wiley

It appears that Valvoline makes two types of racing oil: the stuff in the gray bottle (VR1) and the stuff in the black bottle (available in conventional and synthetic). Both contain zinc.

On the back of the VR1 bottle it states: "For use in high performance passenger cars and race cars" and "API Service SM." The fact that it mentions passenger cars would suggest its ok to use in our cars. No where on the bottle, however, does it say anything about detergents. I'm gonna call their 800 number (1-800-TEAM VAL) tomorrow and ask about detergents, or lack therof, in VR1.

By comparison, the stuff in the black bottle (they don't give it a catchy name like VR1) has "increased amounts of zinc for extra engine protection."

Here is the link to the Valvoline web page that lists their motor oil products. Scroll down the page until you see the Racing Motor Oil section.

B Sieling

Hi Gang,
Like a lot of you I am very dissapointed to find a product we have all trusted for so long has now been "changed" and may actually be bad for our cars now!
I wrote to Red Line from their site and asked for recomendations for my cars. I recieved a vey timmely responce from them.
Attached is the reply I got back from them.
I will be making the change to Red Line!


Thank you for contacting Red Line Oil, you said you had an MG engine
fail, do you know what happened? As you have found many oils
currently available do not provide sufficient protection for flat
tappet cams. The Red Line oils continue to offer very good
protection, we will not reduce those critical levels.

In your TF I would recommend the 10W40 in the engine, MT-90 in the
transmission and 75W90 in the differential.
In the Opel GT the 10W30 would be a good choice if clearances are
reasonable, the MT-90 for the transmission and 75W90 in the
In the TR7 I would recommend the 10W40 in the engine, MTL in the
transmission and 75W90 in the differential.
In the '95 3000GT I would recommend the 10W30 in the engine, the
C+ATF in the automatic transaxle, MT-90 in the transfer case and
75W90 in the differential.
In the '97 3000GT I would recommend the 10W30 in the engine, a
special Diamond SP-III ATF is called for in the automatic transaxle
and we don't offer a cross for that product, the MT-90 for the
transfer case and 75W90 in the differential.

Regards, Dave
Red Line Oil
David Sheward

Damn! It figures. I have a full case of Castrol GTX 20W-50 sitting on the shelf for the TD.

I stopped at Wally World and bought 2 bottles of STP. Interesting, the bottles don't have much information on them. Just a very small "* contains ZDDP..." on the front. Almost too small to be seen!

Evan Ford - TD 27621

For those of you wanting to use Diesel-engine oil a warning is in place: be careful to use it in worn engines, because it contains a lot more "cleaning agents" that may clean away old carbon deposits that helped providing compression and oil-tightness (...)

That "carbibles"-site that Jeff recommends is a big favorite of mine and a real must to read. Not only is his information good, but he writes very funny.
Willem van der Veer

Me too "I have a full case of Castrol GTX 20W-50" ...I bought 2 cases just before this hit the BBS ....looks like my old 92 Dodge Pick up will be running Castroil for some time to come!
By the way did a little looking around and it apears Jeggs is the only full line Red Line dealer near us!
David 55 TF1500 #7427
David Sheward

As per my post below, I called the tech help line at Valvoline. The VR1 Racing oil is fully API rated and contains the detergents needed to keep the engine clean.

He said that their regular oils still contain zinc, albiet a bit lower amount (.08) than before, but still enough for older engines. He said the VR1 has a bit more zinc (.12) than the regular oils and the "racing only" oils in the black bottle, more still. He said the VR1 was not necessary for our engines but certainly would not hurt.

That's what I put in my TD over the weekend but will be checking this thread regularly for more info.

B Sieling

In the UK we have Ultra Low Sulphur Fuel

Mobil testing "lowering the phosphorus content of lubricating oils and the sulphur content of the fuel gave a synergistic benefit, providing the lowest iron content of all even though lowering the sulphur and phosphorus content would have been expected to increase wear as indicated by iron content. This suggests that lubricating oils for use in conjunction with low sulphur fuels can henceforth be formulated with reduced phosphorus levels without adversely affecting wear performance."


Good point, although detergents and disperants tend only to keep clean rather than clean, but there is always a risk even changing to synth from mineral.
Paul Wiley

I'm a bit reluctant to go with Red Line due to increased potential for leakage with synthetic oil. The Valvoline seemed to be a good choice as a conventional oil with the required ZDDP.
B Sieling


I've been looking at some of the oil manufacturers websites, specifically their published MSDS. I'm noting that Zinc (ZDDP) can be a hit or miss proposition depending on the oil in question. I checked out the Chevron MSDS sheets and their Devo 300 and 400 motor oils, as well as their synthetic offering list a Zinc content between 1% to 5% by weight. However their Devo 100 motor oil lists nothing. I found that to be the case with other manufacturers as well. I looked at Valvoline (Ashland) and found the same scenario. I also looked at the MSDS for the Valvoline VR1 racing oil mentioned above and it has something called a "Dispersant Spike" listed as an ingredient. I have no clue as to what that is, but Zinc was not listed.

Think I'll try the STP fix until there is agreement within the group on what qualified oils or additives there really are to use in our cars.


Jim Rice

Valvoline VR1 Racing lists ZDDP right on the container...
Robert Dougherty


Look for Product Information sheet not MSDS
Paul Wiley

Good Morning all
I just sent this email off to Castrol oil products, of which I also have a cabinet full. Enough for about five oil changes in all three cars. Yea I know, I bought it on sale! Here is the email I sent Castrol if they reply Ill post it?

I have used Castrol products in all of my cars for the past 45 years. My father a Canadian used it in his cars before me. I have always had good luck with your products both engine oil and gear oil and grease for the running gear. When looking up the product information sheet and the MSDS sheet for your products as they relate to the amount of zinc in Castrol GTX motor oils, one sheet says 0% Zinc for wear, while the MSDS sheet shows 5-20%. Which is correct. Also this site, which I have linked shows a forum that is viewed by tens of thousands, many of them Castrol users who plan to discontinue use of your products if the zinc content is discontinued. Why wouldn't Castrol products come out with a oil that was for the use in our cars as there are thousands of us world wide. Simply call it "Castrol Classic" for use in classic cars with push rod engines.

This thread appears on the MG cars forum on the BBS site:

If I have sent this to the wrong department of Castrol products, please see that it is pasted along to the correct department. Response back to me by email would be greatly appreciated. John Hambleton

John Hambleton

Simply call it "Castrol Classic"

This exists !
Comes in nice dark green (almost BRG) tin cans, with their 1960s logo. I once bought a litre of gear oil from that range.
Perhaps not for the US market ?
Remo Peter

Thanks Peter, but dose it contain zinc? John
John Hambleton

Here is their answer and very quick. John

Thank you for contacting Castrol North America.

Thank you for contacting Castrol North America.

The GTX Line has a zinc level of 0.075%.

As indicated on our product packaging, the current engine oil category API SM/ILSAC GF-4 is fully backwards compatible or ‘back serviceable’ and has been extensively tested. Valve train issues are not anticipated with the use of modern engine oil in older cars of OEM stock configuration. In fact, current SM/GF-4 engine oils are subjected to testing that is far more intensive than engine oils of previous API/ILSAC categories.

To clarify, in general, ZDDP levels have been reduced a small amount in the current category engine oils (API SM/ILSAC GF-4) in compliance with industry regulations that set maximum levels of Sulphur and Phosphorus, but are still at levels that provide ample engine protection.

Special procedures have always been recommended for the proper initial break-in of a new, matched, cam and lifter set; which include the use of a properly formulated cam break-in lubricant paste which typically contains a healthy dose of molybdenum. Engine oil alone is typically insufficient for break-in of a new cam and lifter set, particularly in a vintage engine type built to historic specifications.

In regards to camshaft failure, Camshaft failure can be attributed to numerous possible causes. Only a thorough analysis of each case can identify the root cause(s) of any failure.

We trust this information addresses your concerns.

Thank you again for your interest in Castrol, The Technology Leader!

Castrol Consumer Relations

John Hambleton

Valve train issues are not anticipated with the use of modern engine oil in older cars of OEM stock configuration. In fact, current SM/GF-4 engine oils are subjected to testing that is far more intensive than engine oils of previous API/ILSAC categories.

I would note the following points
OEM stock configuration.

testing that is far more intensive
In general I would agree with this, however, I'm not convinced re cam wear
SL test
SM test
Harder test but can allow 3x more cam wear for a pass.
Paul Wiley

OK...I checked the product information sheets (at least the ones I could find) and Zinc, if present, is listed...I stand corrected. I run Castrol GTX 10W40 and based on the info John got from has the stuff. The question I have that enough of a percentage to provide adequate protection? I was considering adding STP as well for two reasons. 1) it would seem to raise the percentage thus theoretically providing better protection??...and 2) it would also seem to help quiet the valve train somewhat. I recall years ago that was a claim that STP made. Watching the molassass S L O W L Y pouring out of the cam it sure gave the appearance it would.

Have I been sucked into the advertising pitch or would I actually get better protection and a quieter running engine?


Jim Rice

I've been reading a number of threads about this topic and doing internet research for an answer.

For the U.S., market looks like Valvoline Racing VR1 20W-50 will do nicely. It is API SM/SL/SJ approved so it is for street & track. At $5 a quart, it a bit pricey.

Another choice, not usually suitable for our old cars, are the synthetics like Amsoil, Redline, Royal Purple, & Mobil 1. I found out that Castrol Syntec is NOT a true synthetic motor oil. Only the Castrol SLX 0W-30 made in Germany is.

So, I'm looking at an additive instead. GM EOS, Valvoline Synpower Oil Treatment, and SX-UP (by Specialty Formulations) have been recommended. Here's an oil analysis for the SX-Up:


We had a request to see the elemental analysis for SX-UP from Specialty Formulations. The elements reported are averaged over 5 different lab reports and rounded.

Please recognize that there is more to SX-UP than just these elements. As per our PDS, we also use many ashless organic compounds (not shown on elemental analysis, of course) and agents such as rust inhibitors, Friction Modifiers, Anti-Oxidants, viscosity index improvers, surfactants, metal deactivators for copper (copper corrosion inhibitors), detergents, dispersants, etc. The base oils are PAO's and esters ("Quad-Esters").

Anything less than 10 ppm was ignored.

Molybdenum - 1400 ppm (Friction Reduction, AW, AO)
Boron - 500 ppm (AW, FM)
Tin - 12 (AW)
Phosphorus - 1500 (AW)
Zinc - 2900 (AW)
Calcium - 4200 (Detergent, AW, FM)
Magnesium - 250 (Detergent)

TBN 19.3

KV @100 C - 16.5

This product was originally developed for engine oils in muscle and classic cars from approx. 1955 to about 1980 in order to boost the additive levels of current SF/SH oils to approx. API SD equivalent AW status. The original SD oils had ZDDP levels approximately equivalent to today's HDEO oils.


The SX-UP seems to be the superior additive. It is recommended for gasoline and diesel engines using SAE 10 to 40 weight oils at the rate of 1 pint for every 4 to 5 quarts of oil at oil change. It cost $13-14 a pint.

I think either Castrol or Valvoline 10W-40 plus a pint of SX-UP would get it done. I did find that though both companies have reduced the ZDDP levels, Valvoline retained a smidge more than Castrol.

Also, the European market has motor oils with higher levels of ZDDP than is available here in the U.S.

I found an interesting forum full of gearheads that are quite anal about their oil and have it analyzed regularly:

Carl Floyd


The price I quoted for the Valvoline Racing VR1 20W50 was an internet price from Jeg's (surprised they are that high).

I just called around. It's $3.28 at Advance & $2.79 at Autozone. That is cheaper than adding additives. I'm off to Autozone. My MGs & '68 Camaro (with a very big cam) will be using the Valvoline Racing VR1 20W50

Carl Floyd

Since some of us use Mobil 1 Synthetic 15W50 in our TD's I contacted ExxonMobil to check on the ZDDP level.
Received this answer on 10/19/06 Quote - "The 15W50 has high levels of zinc/phos and has not been reduced and is an excellent choice for your application. If you need further assistance contact ExxonMobil at 1-800-ASK-MOBIL"
Also, I fortunately have not noticed any increased leakage or usage as mentioned by other respondents who tried synthetic oil.

George Metz

[url=]New video-chat site! [/url]
Many new models! New opportunities ( cam to cam, voice chat)!
FREE registration! For all new members FREE 10 minutes private show!

Just for the record: Comma Sonic 20w50 has 0.14% zinc. Just mailed the company and asked them. This oil should be easily available in the UK, and is here in Norway, too.

Statoil ClassicWay has 0.15%, but that is probably available only in Ireland and the Scandinavian countries?


Hi all:

It took a while to reply to my query but here's what BP (Castro) had to say:

I got your voice mail regarding an oil recommendation for an MG. I am very sorry for the delay in replying to this, we have been having problems with the system.

Anyhow, engines such as yours that use flat tappets could be sensitive to reduced levels of Phosphorous in oil formulations, it appears that 0.1% is about the cut off point, so oils for flat tappets should contain >.1%.

Phos has been steadily going down as the amount of ZDDP has been reduced to ensure compatibility with exhaust after treatment

From our range the following are higher than 0.1%

Castrol GTX Diesel 15W-40 (CI4,CH4,CG4,CF4,CF,SL)
Castrol GTX High Mileage 20W-50 (SL,SM)
Castrol GTX 20W-50 (SL,SM)
Castrol HD 30 (SL,SM)
Castrol HD 40 (SL,SM)
Castrol Syntec Blend Truck 15W-40 (CI4,CH4,CG4,CF4,CF,SL)(Semi-synthetic)
Castrol Tection Extra 15W-40 (CI4Plus, CI4,CH4,CG4,CF4,SL)
Castrol Hypuron S 15W-40 (CI4Plus,CH4,CG4,SL)(Semi-synthetic)
Castrol Syntec 5W-40 (SL,CF)(Synthetic)
Castrol GO! 10W-40 Motorcycle Oil (SG)
Castrol GO! 20W-50 Motorcycle Oil (SG)
Castrol Grand Prix 4-Stroke Motorcycle Oil 10W-40 (SG)
Castrol Grand Prix 4-Stroke Motorcycle Oil 20W-50 (SG)
Castrol TWS Motorsport 10W-60 (SJ)(Synthetic)
Jim Rice

This is a little up date, my first post on this issue should have said that the Castrol GTX 10w-30w-oil I use, according to the MSDS sheet from Castrol lists no zinc. The product data sheet lists the zinc level at 0.075. The old Castrol would have had a zinc level of 0.13, so it seems that Castrol cut the zinc level in half. Now if I can only find out when they made this change. Maybe the five oil changes I have stored in the garage are the old formula. I wonder how you could tell. John
John Hambleton

Every can/container will have a 'laser' code on it somewhere, check the number with Castrol and they will give you the date it was made.
gblawson - TD#27667

I think it is interesting that one source at Castrol says that the GTX line is now at 0.075% (SM) about 1/2 of what it was in SJ (and SL?) as reported by John Hambleton, whereas the second source (Jim Rice) admits that the zinc should be above 0.1% for our cars but that the current levels in GTX (SM) is above .1 %. Is he from marketing or just lookung at older specs for SJ and not for SM???

The problem is critical for break in and at least the first 500 miles. There is less data about the effects of long term use since engines using the older formulation would take some time to show the effect of switching to low or no zinc oils.

Even Castrol says use the special hi Zinc stuff on newly rebuilt engines!

Don Harmer

My only reference was that in the first post. I listed the MSDS (Material Data Sheet) both times, when I fu-pawed on the second one and listed the MSDS sheet again. It should have read P.D.S (Product Data Sheet). If you go to the Castrol site the MSDS lists 0 zinc, The PDS lists 0.75. John
John Hambleton

This link

There's this comment:

"The reason zinc content does not mean it is in the form of ZDP, or Zinc Dithiophosphate, the most commonly used anti-wear additive. In other forms, zinc offers additional oxidation protection but little wear control. Second, many other factors such as an oil’s viscometrics and base stock can have a significant effect on wear control. Of course, additives are always important when developing a superior lubricant, but the greatest concern should be developing a formulation that is well balanced from the initial base stock on through the final product."

So, maybe the zinc content isn't enough to go by?


ZDDP is cheap and effective as an anti wear, anti oxidant and anti corrosion additive, but other additives should be added to make up for lack of ZDDP and an ester base oil is an aw additive in its own right.

Detailed explanation

I recognise that this forum is more a compilation of thoughts, but on this topic, might it be possible to come up with some specific suggestions?

What oils currently out there are still being made with a level of additives needed for our engines?

What additives contain those products that we should have in our systems?

This is not a field that I am knowledgable in but I would be willing to assist if data collection is needed.
BEC Cunha

Paul, I keep getting timeout errors when trying to call up that website. Is there another way of access to that info ?
Remo Peter
Steve Simmons

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New oils bad for our biscuit industry?
Rob Edwards

Well with 92+ posts I'm so confused I can hardly stand it. My bottom line is I guess I'll just add a can of SX-UP at each oil change and be done with it. So where do you get SX-UP that's convenient?

Dave C
D Clark

Thank you!

It would be nice if anonymous posts weren't allowed on this site. It might cut down all those spam posts. I wouldn't click the links in those last two!

You can buy SX-up from the manufacturer.
Steve Simmons

Thanks Steve. Somehow I'm a bit (actually a lot) uncomfortable with giving my personal information AND birth date to an online store with no phone number or place of business. I cannot even determine what country their in. I sent them an inquiry as to how else to buy from them but for now I'll just figure out some other solution.

Agreed on the anonymous posts. I took my email off my user info shown because I was getting a lot of junk mail from that.

Dave C
D Clark

on the behalf of Molakule: Speciality Formulations

"We will be ceasing operations today due to our upcoming move.

All orders presently in the Queue will be honored or refunds will be made through Paypal.

At the present time we have no ET on when we will once again resume operations since moving is quite a complex process for a formulating and blending operation.

Many thanks to those who have purchased and used our products and we hope to serve you once again in the future.

Hello MG chaps
This conversation has rippled over to the TRIUMPH TR6 site and has caused a stir.

I too have contacted Castrol and after 3 e-mails finally was told that CASTROL GTX 20W-50 contains .075% ZDDP...NOT .1%.
This is low as even the chap that replied to Jim Rice says that. He kinda shot himself in the foot. It is also amazing that this person (who sounds knowledgeable) does not know the correct concentration of ZDDP in his product and not just ONE product!

Yes it would be a nice world if we could get a list of "approved" oils for our LBCs.

I for one, am looking for a new oil next oil change.

Rick Crawford
'71 TR6
Rick Crawford

I to have wondered over, from the MGA board. My eyes have long since glazed-over, but thank you everyone for your work and input on this subject.

My fairly fresh, engine recently succumbed to unexplainable bearing and cam wear at 13,000 miles. I'm about to start up a fully overhauled MGB engine with a new 270 cam, roller rockers... At this point I am inclined to pour in Valvoline VR1 20-50 with a pint of GM EOS for the break-in. Anybody got any better ideas?

Buy the way, where have you found GM EOS? A Chevy dealer? Thanks agan.

Steve Meline

Another thing. The recent post-mortem on my engine suggested the rings did not properly seat. As mentioned above there has been talk over the years about using non-detergent for break-in. In this light, is there a break-in oil better than Valvoline VR1 20-50?

Steve Meline


Some recommend a non-detergent straight 30w for break-in only. The GM EOS? Yep, a GM/Chevy dealer.

To replace Castrol? Some of my fellow British car club members (& myself) have switched to the Valvoline VR1 20W50. $2.279 @ Autozone.

Some are just pouring in a bottle of STP oil treatment.
Carl Floyd

I have sent a few emails to the various oil companies suggesting a line of 'Vintage' motor oils ... mentioned the huge number of collectors who would snap it up if it was marketed correctly....'duh'.... no interest.
Mark my words...within a year there will be a 'Vintage Oil' product on the shelves and some flunky will be promoted to a VP for coming up with the idea!!!
gblawson - TD#27667


I believe using straight 30W is the most common practice when breaking in a newly rebuilt engine. My engine builder suggested using it for the first 500 miles and then draining it to remove the cam lube that was used as well as any bits of metal shavings/particles worn away during the break-in. After that, any oil of your choice since it's still not clear which one is best.

For the group: Does the oil really need zinc under normal daily operation to adequately protect the engine? I'm trying to recall where I read/heard that the Zinc was there to protect engine surfaces in the event the contact pressure exceeded the oils ability to provide sufficient lubrication. If true, when would that most likely occur? I would think a practice of regular oil changes (3,000 miles or so, maybe sooner), and operating the car as most of us generally do, (except for Matt in such exceedences would be very minimal and the oil would provide adequate protection. If one is continuously pushing the high end of the RPM scale I can envision the potential for metal to metal contact and this is where the zinc would come into play. I'm just surmising on this aspect. Maybe someone can expand on this for the benefit of the group?


Jim Rice

Engine bearings and the piston mostly operate in the "hydrodynamic lubrication" region, where a thick film separates the moving metal surfaces so that there is no chance of them coming into contact. When the pistons are momentarily stationary, however, the layer of oil covering them can be similar in thickness to the surface roughness of the components. In this "mixed lubrication" region, the metal surfaces intermittently come into direct contact. If the thickness of the oil film is much smaller than the surface roughness then the metal surfaces rub together repeatedly - this is known as "boundary lubrication". Contact between the cams and the tappets in the valve train span the mixed and boundary regions.

Consider this for your next oil change. It's what I'm using.
Steve Simmons

can someone advise me of a website or other source of information regarding the ZDDP content of various brands of motor oils and additives? our company has experienced a number of unexplained (to me anyway..) engine failures in our delivery trucks (gas engines)which i believe may be lubricant related, i'm attempting to make some sense of all this.
jerry metcalf

I've been looking at the LUCAS products...?????
gblawson - TD#27667


Tech bulletin from Amsoil

During the development of API SM/ILSAC GF-4 the antiwear requirements of flat tappets were given particular consideration by the engine manufacturers and by the oil industry.Engines with flat tappets were used to qualify API SM/ILSAC GF-4 oils. The anti-wear equirements of these tests are severe.

rebuilt or is modified from stock with highpressure
valve springs, proper precautions should be taken
to insure long camshaft life. These recommendations apply regardless of the lower zinc and phosphorus associated with API SM/ILSAC GF-4 specifications.
Lower quality lifters are increasing in popularity. These lifters may not have the proper metallurgy to withst and long-term service or, in particular, the extra force applied by high-pressure valve springs. Lifter quality should be considered as a contributing factor where excessive wear or premature failure is experienced.

Oil analysis may reveal the cause

Comments from development chemist at Silkolene who owns a Frogeye
In 1960 good quality oil (API SB) would contain some ZDDP of a primitive sort, equivalent to 300-500 parts per million of zinc. Current API SG/SH/SJ oils contain
much superior types of ZDDP at levels equivalent to 1000-1200ppm zinc. The point is, even the reduced ZDDP oils will still contain 600-800ppm zinc, so they'll be much better than any 60's or even 70's oil.
ZDDP is not the only anti-wear compound in modern oils. The sulphur in the calcium or magnesium sulphonate-based detergents (present at high levels in modern oils) also has some anti-wear effect, and some
oils contain phosphorus-free anti-wear agents such as molybdenum dithio-carbamates. Some expensive oils also contain load-carrying synthetic ester lubricants.

HI you h'v very usefull site! thank you and yahoo for mail.


This thread was discussed between 09/10/2006 and 07/01/2007

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.