Are modern oils ruining our engines?

[peecher]

Just read an interesting and alarming thread on the "Lincoln Forum" concerning modern oils and our flat tappet engines. Delta Cam confirmed this problem that the lack of certain additives is causing a large number of cam and lifter failures on rebuilt,flat tappet engines. They recommend the use of Diesel rated oils which still have these additives. you might want to read this thread.

http://www.thelincolnforum.net/phpbb/viewtopic.php?t=18359

Having just rebuilt one V12 and starting on another, this was was indeed important information!

[Centurion]

A similar topic recently appeared on the forums of the Cadillac-LaSalle Club.

Denny Manner is a retired engine engineer for Buick Motor Division. He designed and developed engines for Buick/General Motors from the 1960's to the mid-1990's, and has collected old cars for almost 30 years. At last summer's Buick Nationals in Rochester, Minnesota, Manner made the following comments:

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Use GM Engine Oil Supplement (E.O.S.) GM part no. 1052367 in pre-1986 Buick engines. Flat lifters (pre 1986) and aluminum rocker arms (pre 1973) in our Buick collector car engines operate with very thin oil films and require zinc additive in the oil for wear protection. Unfortunately, today's oil designed for modern engines with roller lifters and roller rocker arms have lower quantitities of anti-wear zinc additive. I recommend using a pint of E.O.S. (basically a zinc additive) with each oild change but don't overfill the crankcase. E.O.S. is also an excellent prelube to use during engine assembly of camshaft, lifters and rocker arm assemblies. Some of today's oils have adequate levels of zinc, generally racing oils and oil certified for both diesel and gasoline engines -- I choose to include a pint of E.O.S. with each oil change and be assured of wear protection.</div></div>

[zman]

I use the 15/40 with a quart of Reslone.

Reslone has been around for 50 or 60 years,

and used by Ford garages for break-in of engines too

Bill

[DizzyDale]

Dear Brian,I went to the local Chevy dealer to buy the additive Mr. Manners mentions in the article.Parts guy knew what i was talking about and gave me the correct part number and in the same breath told me the name was changed to BREAK IN oil BUT did not know if the formula was changed along with the name..Anybody got any info on GM BREAK IN oil???I wanna put it in my 39 Zephyr and 62 Corvette with the solid lifter camshaft.diz

[Centurion]

DizzyDale, if you read through the comments linked above from the Lincoln-Continental Owners Club forums, I believe you'll see that GM is unable to promote this as an engine oil supplement. The reason is that the zinc is destructive to catalytic converters installed on 1975-and-newer model cars. Obviously, that's not an issue for our pre-1975 model year collector cars. The message I'm getting is that a zinc supplement like this is something we'd want to utilize on a regular basis for the older cars, given the changing composition of modern motor oils.

[Guest Mims]

While I am no longer in the Lincoln business I have read a few articles on this in Hot Rod Magazine for one and had some experience as with Air Emissions and Diesel engines in the last few years. OK, here goes, this is my personal opinion. The engines being manufactured today have closer tolerances due to all of the computer systems used for machining versus what was produced years ago. Hot Rod Magazine mentioned a while back that the oils now being used have less or different additives in them due to the tighter emissions laws for vehicles. Thus you have tighter clearances on the flat cam tappets or lifters and the cams versus what was produced years ago. Probably an earlier engine is going to or may chew the lobes on the cam due to oil design and looser tolerances. The oils today with the additives are less forgiving due to possibly being thinner or less lubricant due to the deletion of the additives. A flat lifter/cam is going to have a higher coefficient of static friction (engineering term) versus a roller lifter or tappet/cam. One question that I have is have the Society of Automotive Engineers (SAE) standards for oil changed in the last few years.

Hot Rod Magazine in two different articles has mentioned using the Shell Rotella oil for engines. This is the diesel engine oil. My thinking is that the reason for using the oil is that there are more lubricant additives in the oil versus regular gasoline engine/type oil. Diesel engines on road and off road have higher emission limits for NOX and other things versus gasoline engines and have had for years, thus they can still put things in the additives for oil. They have lowered the emission limits for new diesel engines on and off road and this may change over the next few years.

In the October 2006 issue of Hot Rod Magazine they have rebuilt a " Junk Yard Jewel " Pontiac 400 engine and use the Shell Rotella oil. There is an earlier article on the cams and oil but I have thrown out the article.

Anyway, Shell has the oil available at www.rotella.com in grades 15w-40 and 10w-30. That's my two cents worth of thought on this subject. Let me know what you guys think.

Thanks,

Mims