Oil for pre-war cars

[bob duffer]

I have talked to a few people about what kind of oil they use in there cars so, i'll ask here too

to see what everyone uses. I have a 34 Buick model 50. What kind of oil should i use?

I don't know anything about the work that has been done to the engine and i live in Michigan.

[CarNucopia]

I asked the same question a few months ago. Here's the thread: http://forums.aaca.org/f165/oil-do-you-recommend-382002.html

[Marty Roth]

Bob,

I'm using "old formula" 20 Weight or 30W Non-Detergent in my 1937 all-original unrestored Roadmaster.

My 1934 50 series - identical to yours, but fully-restored has "Insert Bearings" and is treated to Rotella 15W-40 , same as my diesels because it has better Zinc properties.

I use 85-140 in the transmission and differential

[bob duffer]

I just got in touch with the 4th owner of my car because of a magazine i found under the rear seat with his postal tag on it from British Columbia .

He said he had the engine rebuilt to org. factory specs in 1998 .So ,would that make a difference in the oil i use because there was there was nothing extra

done to the engine?

[Marty Roth]

In your case, since it has been 18 years, I would drop the pan and ensure that all is clean and that no sludge has built up. I would then use Shell Rotella (or comparable) 15W-40 as used in modern Diesel car and truck engines because they have better properties comparable to the way your car was designed (and possibly more zinc) although many will argue this point - still, it cannot hurt, and may likely help.

Good luck Bob,

Marty

Edited January 3, 2015 by Marty Roth
typo - afterthought (see edit history)

[bob duffer]

Thank you Marty.