Good topic here GordonM. I highly recommend that bobistheoilguy site. Very informative reading over there. I am using the Valvoline race oil. Not the VR1 but the race oil. They make it in both Dino and Synthetic. That is what my engine builder recommended in my big flat tappet cammed engine.

 

very interesting topic.

who says you cant teach an old dog new tricks

 

Way too confusing for me and no solid proof anywhere on anything ...everything can be swayed or biased to look favorable or unfavorable.........Walmart stuff (valvoline, castrol, etc) has worked well for me for the past 35 years -- as said before, just change it regularly.

 

I play golf occasionally with the local Mobil1 rep. His take was that the synthetics are primarily designed for the newer design motors as their tolerances are much closer and need the advantages afforded by synthetics. That's why they are std on most high performance engines. MB, BMW etc.

For our gen of engines rebuilt or not, the higher quality oils are sufficient and in fact prefered. He did say that running diesel oils in the proper wt ranges wouldn't hurt and do contain more additives. He did stress that frequent oil changes were called for to decrease wear and etc.

I personally use Chevron 10-30 Diesel in my C3 and Mobile1 in my C6.

My opinion.

 

Delo 400 15w-45 Diesel oil is great for a southern engine. You snow birds might need something different.

 

So, for both my '80 L48 and my '69 L46, I should be using what oil? Neither has had a rebuild recently with exception of the L48 back in 1999.

Are y'all saying dino motor oils, without additional additives purchased separately, are now BAD for our engines (ruining cams?)?

Both cars have the flat, hydraulic tappet cams.

Don't tell me I have to spend extra $$$ on racing oils or diesel oils. How can the 1,000's of engines that are sold in the aftermarket have non-roller cams and be viable?

 

Ted,

I get the Rotella T at the farm supply store, its cheaper by the gallon than getting quarts at Walmart for the name brand good stuff.

 

What's the approx $/quart cost of the different oils (Rotella T for example)? I'd heard about the zinc issue but I just assumed it was more an issue if the cam is new and less of an issue once the engine is broken in.

Am I wrong here?

 

Ted, I think there's still some off the shelf dino oils that fit the bill for our older engines. After a lot of reading on the BITOG forum I realized the the garden variety Valvoline I was using wasn't highly thought of by the experts there. I have since changed to the Valvoline Maxlife...still a dino, but with a better additive pack. The Valvoline race oils (dino and synthetic) are also good.

 

No not at all. I think the Dino oils are probably better for older engines than the synthetics as far as lubricating the engine and our needs. The synthetics are not doubt better for newer engines with tight tolerances. The newer style Dino oils are now being made with less of the additives due to the EPA and trying to get cleaner air. They do not care about our older engines. The deisel oil and racing dino oils are not that much more expensive than standard oils. The sythetics are quite a bit more. I think I'll be running some of the racing Dino oils in mine from now on. Good info has been given here. This is what I was hoping to find out.

 

Several of the bigger oil companies are now making oils specially blended for older and high milage engines. I would use one of those.

 

Here's a reply to this question I posted to the Amsoil tech site:

"In general, it is true that diesel formulas are allowed more anti-wear additives such as ZDDP or other newer additive technologies. It is also true that flat tappet engines require a higher level of anti-wear additives. Zinc works very well as an anti-wear additive but is rapidly being replaced with newer high-performance AW compounds. It is not necessary to use diesel oil if you were to use one of our high performance oils such as our AMSOIL ATM 10W30 Turbo formula. We have not lowered the levels of anti-wear additives in this formulation and we also incorporate newer anti-wear additive technology that is very effective for protecting this type of application."

 

All synthetics do not use the same Group I and II base stocks. Here is a quick synopsis of the "synthetic" oil base stock groups.

Though most people recognize that there is a difference between petroleum oil, semi-synthetic blends, and synthetic oils, they do not realize that there are significant variations between synthetic oils. The American Petroleum Institute (API) has not come out and defined what is "synthetic", but rather, classified oils into five major groups:

- Group I base oils are the least refined of all of the groups. They are usually a mix of different hydrocarbon chains with little or no uniformity. While some automotive oils use these stocks, they are generally used in less demanding applications.

- Group II base oils are common in mineral based motor oils. They have fair to good performance in the areas of volatility, oxidation stability, wear prevention and flash/fire points. They have only fair performance in areas such as pour point and cold crank viscosity. Group II base stocks are what the majority of engine oils are made from. 3000 mile oil changes are the norm.

- Group III base oils are subjected to the highest level of refining of all the mineral oil stocks. Although not chemically engineered, they offer improved performance in a wide range of areas as well as good molecular uniformity and stability. By definition they are considered a synthesized material and can be used in the production of synthetic and semi-synthetic lubricants. Group III is used in the vast majority of full synthetics or synthetic blends. They are superior to Group I and II oils but still have limitations. Some formulations are designed for extended oil changes. AMSOIL XL Synthetic, Castrol Syntec and most other synthetic oils on the market fall into this group.

- Group IV base oils are comprised of polyalphaolefins (PAO), a chemically engineered synthesized base stock. PAOs offer excellent stability, molecular uniformity and performance over a wide range of lubricating properties. AMSOIL Series 2000/3000 and SAE Synthetics, and Mobil 1 are Group IV synthetic oils.

- Group V base oils are also chemically engineered stocks that do not fall into any of the categories previously mentioned. Typical examples of Group V stocks are Esters, polyglycols and silicone. Redline Racing oils use an Ester base stock and are Group V synthetic oils.

As to whether the additive package in SM/GF-4 oils is "better" is subject to debate. Though the new SM/GF-4 standards have higher performance standards than older standards, they actually severely restrict ZDDP additives (by limiting phosphorus to 0.08%). This was done at the behest of the automotive industry to help them meet EPA requirements, not protect the engine.
You can read the ILSAC GF-4 standards here:
http://www.ilma.org/resources/ilsac_finalstd011404.pdf
You can see the EPAs impact on the auto industry in this letter:
http://www.ilma.org/resources/gf4letter.pdf
And you can read the history, including the why the auto industry and the EPA wanted the new standard here:
http://www.northamericanlubricants.c...s/gf4specs.htm

For those that desire a high quality diesel oil for their engines, I suggest these depending on your weight preference (I use the 5w30 in my F350):
AMSOIL Series 3000 Synthetic 5w30 Heavy Duty Diesel Oil
AMSOIL SAE 15w40 Heavy Duty Diesel Oil

But, despite the new standards, AMSOIL does make some excellent oils for gasoline engines as indicated by the above quote. I'd recommend one of these three Group IV PAO based synthetics for those looking for a good gasoline engine synthetic:
AMSOIL Series 2000 0w30
AMSOIL SAE Synthetic 10w30
AMSOIL SAE Synthetic High Performance 10w40 (I used this in my car at an SCCA race last weekend in SC. I'll shift to a 20w50 when it gets hotter later in the season)

 

Good info Subdriver. This is the kind of information I am looking for.

 

My information will be a little old because it recalls research and results from oil tests I was directly involved with in 2000. I still have all of the records back at the office but I will attempt to recall what I can for now; the names of some of the chemicals might need correcting; it's been 6 years. We were required to use a certain brand exclusively due to contractural reasons and began experiencing increasing problems that affected our entire operation. There are three main areas in an engine that are difficult to lubricate: The top ring to ring land sliding contact surface, the piston wrist pin bores, and the cam lobes in a flat tappet engine. The problem is in achieving an adequate supply of lubricant to these remote high heat/ pressure or extreme pressure areas. In the case of top rings in a high output engine under full load microwelding can occur due to high heat and pressure which was the problem we needed to solve at the time. The top ring literally tries to weld to the bottom ring land and both surfaces are quickly destroyed, usually in the initial stages of dyno testing and validation. Phosphate coatings on rings help but because it is a difficult critical area to lubricate oil chemistry plays a vital role. We learned most oil brands do not own an oil refinery but are simply repackagers and marketing companies. This was true of the brand we were using at the time and we soon discovered in addition to that they did not have an oil engineer or chemist on staff who could adequately explain the interacting roles of the additive package and how to adjust the concentration of additives for a custom mix that would help solve the problem. This may have been about the time levels of ZDDP was reduced in all oils to help address catalytic converter poisoning. All the teams were having this problem at the time but GM commissioned a dedicated test in conjunction with the chemists from Unocal to look into it; much testing was done and a lot was learned from it. Microwelding occurs on the molecular level and the chemistry that prevents it is only a few atoms thick. Phosphates from ZDDP in the oil react under high heat and pressure to deposit sulfate atoms on the sliding contact surfaces. These sulfates are sacrificed in place of base metal and are constantly replenished by the additives in the oil until the supply is depleted. Oil chemistry is pretty demanding when you look at all of the results the oil companies are trying to achieve in one package. We learned for example, an oils detergent package can be made up several different ways. One way may work in harmony with other chemistry to promote sulfates at the critical areas but another package blend could promote the formation of destructive sulfides rather than the desired sulfates. This is why you don't want to just pour an additive in because you don't know for sure what it will do under extreme heat and pressure unless you test to find out. A special Unocal 10-30 Racing oil was designed by the chemists as a result of our testing in 2000 and it saved the day for us then which was for the Daytona 500 at the time; all engines made it OK and were fine afterwards. Since then we solved the problem our brand didn't address at the time and different things are at the top of our list now. I mainly addressed the top ring area in a racing engine but the wrist pin bores and cam lobes are just as critical especially with high lifts and strong springs.

Regards, Greg

 

That's great info Greg.

To ensure there is no confusion regarding whether AMSOIL just markets oil produced by other companies (as many probably do as Greg alludes to)...

AMSOIL doesn't have a refinery. They buy top quality Group III basestock from major oil companies for their least expensive line, the AMSOIL XL Motor Oils. They buy Group IV PAO basestock from major oil companies such as Exxon/Mobil for their main lines of synthetics, the AMSOIL Series 2000 Motor Oils and the AMSOIL SAE Synthetic Motor Oils.

AMSOIL does have an extensive staff of chemists that study and determine the additive packages required to make their oils perform well in a process similar to that discribed above by Greg. AMSOIL has its own blending plant in Superior WI and determines and adds their own additives to the Group III and Group IV basestocks they buy.

And finally, as Greg described, making an oil work well isn't as easy as just pouring in additives. How these additives work with the basestock and the other additives is key to success. To highlight this issue, take a look at the results of the four ball wear test on page 13 of this independent lab test of motor cycle oils commissioned by AMSOIL:
AMSOIL Motorcycle Oil “White Paper” (1 MB pdf file)

This test shows that high levels of ZDDP by themselves don't ensure success. For those that can't download this, here is a quote:

"The ASTM D-4172 4-Ball Wear Test is a good measure of the existence and robustness of an oil's additive chemistry. It is used to determine an oil’s ability to minimize wear in case of metal-to-metal contact. The test consists of a steel ball that sits atop three identical ***** that have been placed in a triangular pattern and restrained from moving. All four ***** are immersed in the test oil, which is heated and maintained at a constant temperature. The upper ball is then rotated and forced onto the lower three ***** with a load measured in kilogram-force (kgf). After a one-hour period of constant load, speed and temperature, the lower three ***** are inspected at the point of contact. Any wear will appear as a single scar on each of the lower *****. The diameter of the scar is measured on each of the lower ***** and the results are reported as the average of the three scars, expressed in millimeters. The lower the average scar diameter, the better the wear protection of the oil. In this case, the load, speed and temperature used for the test were 40 kg, 1800 RPMs and 150° C respectively.

Interestingly, the SAE 40 oils with the highest and lowest levels of zinc, Maxima Maxum 4 at 2,464 ppm and Pennzoil Motorcycle at 1,010 ppm, had identical results. Royal Purple, with an average level of zinc (1,474 ppm) had the largest wear scar (nearly 55% larger than the next closest wear scar size). Zinc levels for those oils performing the best, AMSOIL MCF, Mobil 1 MX4T, Motul 300V Sport and Torco T-4SR ranged from 1,061 to 1,762 ppm. The SAE 50 group showed a similar trend. Golden Spectro 4, with the highest zinc level (2,162 ppm), performed less than average in the 4-Ball Wear Test, while the Motul 300 V Competition, with the lowest zinc level (1,048 ppm), tied with AMSOIL MCV and Torco T 4SR with the best test results. The results strongly suggest that simply having high levels of zinc is not sufficient to effectively minimize wear."

 

sorry to resurrect a semi older thread, but i understand very little of what was just said.

with that said, im looking for recomendations on what to use with my up comeing oil change.

its for a 69 350/300 that hasnt been rebuilt for alteast 25 years, and has 65K miles on it. the car probably will get driven 2-3 times a week, about 20-25 miles each time.

what about this Royal Purple stuff that ive seen so many people raveing about. is this stuff really that good or just overpriced hype?

 

Key words:

"The results strongly suggest that simply having high levels of zinc is not sufficient to effectively minimize wear."

 

royal purple is an expensive oil from racing stores, its good stuff just like redline and others...your choices are limitless onthe oils...you want a recommendation buy valvoline racing oil in 10w 30 to start and if yu have a high consumption go to 10w40....another suggestion by any name brand oil that says "racing formula" ...another suggestion buy regular off the shelf oil and add the GM EOS supplement....the possibilites go on forever....

 

Probably going to stir something up here, but anyways, I wouldn't use a synthetic in a 25 year old, 65k engine. The synthetic's additives could affect the older seals and cause leaks to occur. There is much debate on this, but if it were me I would go with Race oil or possibly Delo 400 or Shell Rotella 15w-40 dino oil.