My Dad used to say that he ran a little thicker oil because it circulated a little more slowly so it was able to take more heat out of the areas it was lubricating, then stay in the pan a little longer to help dissipate it. I don't know how true that is, but every engine he ever owned saw the high side of 300K miles. Unless it was already worn out when he got it, that is.
It's interesting to note that the big inch Cadillac V8s (368-425-472-500) only had about 40psi from the factory. Those engines have a lot of bearing surface area-more than a big block Chevy or even a Pontiac, so the lower speed of oil going through everything would tend to bear his theory out. The only Cadillac V8 I ever knew that had a lubrication related failure, was the one with the aftermarket pump set to 60psi. It froze up solid on me, on the way to St. Louis. That was an expensive tow.
So after that, I went back to the factory aluminum housing oil pump that puts out 42psi on a cold day, 38 on a really hot day, and have had many trouble free miles with said Cadillac V8 pushing a 15,000lb converted school bus around.
Last edited by Tronman; 09/07/2023 4:14 AM.
