Oil Type

I use Walmart blue jugs of non-synthetic 10W-40 in all my old cars. It is now certified as SM, which is about 10 generations better than the oil our cars were designed to use. 10W-30 will work well, too, especially in colder climates.


Edited by 6768rogues - Mar/29/2012 at 5:56pm

all modern oils are so much better than the old days! there's a lot of controversy about oils and i don't want to add to it, but the upshot is, decent quality and frequent changes and you're fine. modern oils don't have zinc (ZDDP) additives any more but consensus seems to be, once an engine is broken in, the lack thereof doesn't hurt longevity.

some people claim that switching an old engine to synthetics loosens up lots of gunk, but that's anecdotal, i've personally seen no evidence tho i'm not doubting it either.

if you do a rebuild, then it's totally worth switching to synthetics, they are vastly superior. for large-clearance engines like ours, Mobil 1's 15W-50 is designed for them, is more or less equivelant to regular 10W-30, and actually has some ZDDP in it. NAPA carries it. some people run certain diesel oils that still contain zinc.

Rebuilds need a serious zinc additive to break in flat-tappet cams and lifters.

Thanks Guys.