I was wondering, what is the preferred engine oil and filter, you are running in your 72' Buick motors? Someone, before suggested diesel oil. Rotella T 15W-40.
Only if you're putting diesel fuel in the tank also. Use hi zinc gas engine motor oil like Valvoline VR1. use no thicker than 10w30. Use Purolater Pure one gold filter.
I've tried all different weights thru the years, even straight 50 waay back when. I've learned a lot and noticed a lot. 10/30 is perfect if your bearing clearances and oil pump are correct. 10/40 is ok too, that's what Buick recommended in the '70's Any heavier is a band aid for issues. Wix, Napa, or Purolator, even the smaller Purolator that's the size of an AC PF51 is good.
Jim Wiese recommended the Joe Gibbs 10W/30 for my new engine, and that is what I have used ever since. I used the conventional oil for the first year. I then switched over to the synthetic version of that oil. https://www.summitracing.com/parts/...n-racing-oil&gclid=COPugIX_t9MCFUlXDQodfScFMw https://www.summitracing.com/parts/jgr-01506/overview/
To answer your first post, Shell says "Shell Rotella T Multigrade Oil SAE 15W-40 with Triple Protection Technology, our API CJ-4/SM specification product, typically contains about 1200 ppm zinc and 1100 ppm phosphorous as manufactured" so people recommend it because of the zinc. Diesels don't have cat's so they still have zinc in the diesels oil.
Diesels do have cats . In the after treatment systems and the light duty trucks(f250/350,450,2500,3500) has had cats since 1999 15-40 is pretty thick for temps out side now. Unless you in 90 plus you ain't needing it
My old girl has 136,000 original miles! Bought her last January 2016. She broke a water pump, in April of 2016'. And has been down since, April of this year. During that time, new water pump, timing cover bought off V8 buick forum ( Sweet!!!) 100 amp alternator, 900 Frank Battery. Oil pan, valve cover, and transmission gaskets, No problems!. I will post pics of engine I degreased and cleaned up. Painted engine, exhaust, bay area and under hood, came out real good!. So, I just wanted to use the weight oil, with the mileage. Thanks to all, be safe!, you and your Family's. Dana
Diesel exhaust fluid, and a regeneration process the fuels the cat to 600 plus degrees and burns excess soot. .
A while back I was talking with a guy who has done a lot of research and development on oils and he mentioned that diesel oils don't have an anti-foaming agent in them, which makes them undesirable for passenger car engines, particularly those who see higher rpm use. True/False? I'm not an oil expert so I'm just passing this along.
