The Stovebolt Site Forums The Shop Area Engine Shop Oil Question

I've rebuilt a 1952 Chevy 216. Two questions: (1) Would it be good to use synthetic oil (Mobil - which I understand is a synthetic/regular oil mix)? If yes, how many miles should I wait in using the synthetic oil, to let everything seat-in (with regular oil)? (2)If "no" to the above, is it now okay for me to use regular detergent oil, vrs. non-detergent? Thanks. Bob

Opinions about oil on this site are like - - - -uh- - - -"noses". Everybody's got one and some of them are pretty smelly! My personal opinion is that a straight-weight high detergent mineral oil like 20 or 30 weight would be my first choice, followed by a 15W-30 Diesel rated oil if there was some reason to run a multi-grade. The clearances in stovebolt engines do not seem to work well with very low-viscosity oils like 5W-30, etc. I don't know of any oil manufacturer that sells a straight-weight synthetic.

Duck and cover- - - -let the flaming begin!
Jerry

The old things ran a long time on single weight oil. I still believe in breaking them in on a 20 weight non detergent, but it is hard to find. A single weight oil would be my second choice and it is still available. I always add ZDDP to any engine with flat tappets. Once they are broken in, Mobil one makes a high mileage oil.

https://mobiloil.com/en/motor-oils/mobil-1/mobil-1-high-mileage

It seems to work quite well in old engines and extends the drain intervals a lot. I am hesitant to recommend a Diesel oil because Diesel generates different contaminants than a gasoline engines. But that doesn't keep a lot of guys from using Rotella 15W40.

Like Jerry says, this is a very controversial subject. I think everyone will agree that you don't want a synthetic designed for modern cars.

In my 54 car and my old 235 I ran straight 30 Rotella. The motor was old and tired, so I'm sure it was just happy to have any oil. I used rotella based on recommendation because of the slightly higher zinc levels. It could all be b.s. for all I know. I just replaced that motor with a rebuilt 235 that I got from Tom Langdon. He recommended using any regular 5w-30 or 10w-30 motor oil. I opted to go with Brad Penn 10w-30 motor oil. Is it necessary, I don't know, but the price isn't much different so I figure it's also not going to hurt. Just my 2 cents. To each their own, but I would stay away from the synthetic.

I run 15/40 rotella in every vehicle i own. From my 1942 chevy, to my wifes 2006 4-runner, no problems in any.