72 250 what oil

[rosenfe]

I assume non synthetic 5/30
If so what brands?

[Todd Miller]

5w/30 would be far too thin.

Use 20w/50 in something that contains significant zinc. Zinc has been removed from modern oils so as not to harm the catalytic converters, but it's very important in older engine designs

[Sugar Bear]

I'd use Rotella T non-synthetic in the summer and a 10W-30 of that in the winter.

[Todd Miller]

The cold start temp range of 20w/50 will be fine in Fairfax, CA if the car is actually driven in the dead of the winter there.

[subforry]

Shell Rotella T4, 15w-40. It's inexpensive and has the required zinc. As for the weight, I used to go with 20w-50, but now I think it's unnecessarily heavy, and I live in CA. As long as you are getting 10+psi at idle and pinned at cruise, it's fine.