5w30 or 10w30 it really doesn't matter. As an engine wears and internal tolerances increase, you may wish to switch to a heavier oil, like 20w50. That is what I run in pretty much anything with over 100k miles. I have heard that 15w40 Heavy-Duty Diesel oil is the shiznit for cutting down on oil burning. To get that stuff you have to go to a dealer, local parts place won't have it. I know my local Ford and GMC dealers do. I have heard wonder stories about it, but I used it once and it didn't seem to be any better than the 20w50 I had always used.