Note that this article was published in November 2006 and is offered here to provide background to the problem of changing oil formulations. More recent information can be found in the follow-up article located at the Continued… link which is also located at the bottom of this article.

By: Keith Ansell, Foreign Parts Positively, Inc.

About a year ago I read about the reduction of zinc dialkyl 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 sup-plied oils was based on the fact that phosphates reduce the effectiveness and eventually damage catalytic converters and introduce minute amounts of pollutants into our atmosphere.

A couple of months 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 ( Delta Cam ) 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 as-sembly lubricant, at assembly, was about the only thing that could create this type of prob-lem. My customer has assembled many engines and had lubricated the camshaft properly. Then the bad news came out: It’s today’s “modern” API ( American Petroleum Industry ) approved oils that are killing our engines: Meaning all flat tappet ( cam follower ) equipped engines, as used in all BMC products, all British Leyland products, most pushrod engines prior to 1980, early Volvos, American high-performance en-gines and many others.

Next call: To a 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 won’t 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 ( Red Line Oil ). 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 don’t 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, doesn’t 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 flattappet  en-gines. 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 recommendding 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 needs the additive but remain skeptical that the first oil is all that is necessary. Their suggestion is to use diesel rated oils such as Delo or Rotella that are usual-ly 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 man-ufacturer. The 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 couldn’t 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 as-sembly lube  and an oil additive. The telling sen-tence 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 the shelf 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 have the ZDDP we need in weights we are familiar with.

From one camshaft manufacturer ( Crane ): “use our additive” for the first 500 miles.

From General Motors ( Chevrolet ): add EOS, their oil fortifier, to your oil, it’s only an 8-ounce can ( This problem seems to be something GM has known about for some time! ).  The ad-ditive says for break-in only, some dealers add it to every oil change.

From Redline Oil: Use our street formulated synthetics. They have what we need! Early in 2007 they will be supplying a “break-in oil” specifically for our cars.

From Castrol: We are beginning to see a pattern emerging on older cars. It may be advantageous to use a non-approvedlubricant, such as oils that are Diesel rated, 4 Cycle Motorcycle oils and other specified diesel oils. They will be supplying “new oils” specifically for our cars in early 2007.

For you science buffs: ZDDP is a single polar molecule that is attracted to Iron based metals. The one polar end tends to “Stand” the mol-ecule up on the metal surface that it is bonded to by heat and friction. This forms a sacrificial layer to protect the base metals of the cam and tappet from contacting each other. Only at very high pressures on a flat tappet cam is this necessary because the oil is squeezed or wiped from the surface. This high pressure is also present on the gudgeon pin ( wrist pin ) in diesel engines, therefore the need for ZDDP in all diesel engines.

The Second part of the equation is Molybden-um disulfide ( Moly ). The molybonds to the zinc adding an additional, very slippery, sacrificial layer to the metal. I found out that too much of the moly will create problems; lack of this ma-terial reduces the effectiveness of the ZDDP. The percentage, by weight is from .01 to .02%, not much, but necessary according to the chemists.

Now there is no denying that there is a prob-lem, lack of ZDDP ( Zinc-Dialkyl-Dithio-Phos-phate ) in modern oils kills at least our cams and tappets. There seems to be no known alter-native.

Our cars are a small percentage of the total market and BIG Corporate, the American Petroleum Institute and possibly government have made decisions that are detrimental to our cars. This problem isn’t going away. The trend today is to lighter weight oils to decrease drag, which increases mileage. Most of these seem to be the “Energy Conservation” oils that we can-not use.

Redline oil and others are suggesting a 3,000 mile break-in for new engines! Proper seating of rings with today’s lubricants is taking that long to properly seal. Shifting to synthetics be-fore that time will just burn a lot of oil and not run as well as hoped.

The “Energy Conservation” trend was first led by automakers to increase mileage numbers and secondly because the ZDDP and other chem-icals degrade the catalytic converter after extended miles, increasing pollution. Most of us don’t have catalytic converters and the mileage gains are not that significant.

Many oil companies may have products that will continue to function well in our cars. Castrol, Redline, Valvoline, Mobil, Shell, Ams-oil and others have now commented on my original article and are making suggestions. Some companies are offering short lists of “acceptable” oils, others just one. One comp-any has responded without any substantive information in a two page “bulletin”. By their account all their oils are superior and applicable. This is typical of many companies.

Some oil manufacturers are pointing to metal-lurgy, blaming poorly built cams and followers. This may have some validity but the bottom line is that there has been a big increase in failures with products that have been on the market for many years but are now having greatly in-creased failures. To me the bottom line is, if the lubricants are working there is no contact be-tween surfaces, it shouldn’t matter what the materials used in the products are, within rea-son.

On “modern” production cars, stay with the manufacturers’ suggestions. For any car pro-duced before about 1990 the owner needs to be aware that the factory suggested lubricant may have changed and may not be applicable. Flat tappet, stock, performance or modified may be affected. MGBs from 1975 to 1980 must choose to sacrifice the cam or the catalytic converter as an example of how difficult the decisions are becoming!

Yes, there is more! Castrol does understand our dilemma and is actively looking into what it can do to support our cars. We can soon ex-pect to see products from them with specific application to classic cars. Red Line will be of-fering a “break-in” oil soon after the first of the year. Shell’s Rotella will be good until about June or July of 2007 with possibly nothing after that date. Delo ( Chevron ) will also be questionable after the new “CJ-4” standards come in the middle of 2007.

Now the important information, here are Oils that may be correct for our cars today:

( As reported by manufacturers by 2-18-07, NOTE: many have changed their recom-mendations over the last three months! )

 Castrol Syntec “Classic” 20W-50
( available after April, 2007 )

TWS Motorsport: 10W-60*

BMW:       Long Life 5W-30*

Red Line:  10W-30, 10W-40
( Synthetic oils )

Valvoline: VR-1 20W-50
( Conventional oil )

Amsoil:      20W-50 ( TRO ),
10W-40 ( AMO ),
15W-40 ( AME ) &
20W-50 ( ARO )

Mobil:        Mobil 1 5W-30
20W-50 ( Synthetic )

Chevron:   Delo 400

Shell:         Rotella

* full synthetic, available only at BMW dealerships

What we are doing at Foreign Parts Positively has been difficult to determine but with few options left, the following is what we are forced to do. Some of our choices have been based on the manufacturer’s willingness to help and specific reports. This list will change in the next months with Castrol and Red Line adding products just for our cars.

  • Break-in uses Delo 400 30W ( abreak-in oil will be available from Redline soon! ) or Castrol HD-30 if it was pro-duced before July 2006. We have some old stock of Castrol HD-30.
  • Conventional oil is Valvoline VR-1 20W-50 or Castrol GTX-20w-50 if it was  produced before July 2006. We have some old stock.
  • Synthetic oil is Red Line 10W-30 in newer engines or 10W-40 in older en-gines.
  • Break-in is now 3,000 miles before changeover to running oil.
  • 1-year or 18,000 mile oil change interval with Red Line synthetic
  • 1-year or 2,500 mile oil change interval with conventional oil ( Val-voline VR-1 20W-50 ).

Thank you to Castrol, Redline, Christiansen Oil, Valvoline, Mobil, Shell, Standard Oil and Amsoil for input. We’re sure this subject will continue: Please forward any new information on this subject that you may encounter.

We have received some very interesting ma-terial from “Mr Moly” that may be putting molybdenum disulfide ( MoS ) into this discussion. It seems that ZDDP plus MoS is the best from the oil companies’ opinion but MoS by itself may be beneficial. Some racers swear by it. The literature seems to support “Mr. Moly’s” position.

Keith M. Ansell
Foreign Parts Positively, Inc.
[email protected]