So now that I can drive the truck I first want to get oils changed.. any recommendations - motors actually a 1973 or so 292 now, not certain of 4 speed tranny, and rear end is a vacuum shift 2 speed GMC which I think is original.
I've read that engine oil for a diesel has more zinc in it, or regular oil plus additive best?
For tranny, and rear end I'm planning standard 80w90..
Being for the big bolt posted here, but let me know if moving to engine or driveline forums best...
