I'll through my two cents in here, which is about twice what they're worth! The whole 5wXX thing has come from the desire to improve CAFE fuel mileage. I've heard of a fair number of "off the record" suggestions from factory shops saying that you're better off running 10wXX unless you're operating in cold winter conditions. And that only applies to fairly new engines, that are machined with modern tolerances. Personally, I'd never go lighter than 10w in an AMC. The same theories hold true in Trany oil. The old school was 90w, but a lot of trany's are now calling for standard engine oil. You have to read the specs. You can kill a trany that needs 30w by putting 90w into it, and the opposite is true as well. Again, part of the reason for the lighter weight is fuel economy, but don't go overboard! Some parts need a certain amount of drag in order to function properly (like syncro's). And last by not least, change your oil (engine, trany, diff) often, and don't cheap out! Just because a synthetic oil maintains it's grade longer doesn't mean you can stretch the change intervals (inspite of what most people tell you). The oil may be good, but it's also full of crap that you don't want to keep in your motor! And if you do the math, a few more oil changes over the life time cost of the vehicle is chump change. I'll step off my soap box now! Dave _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://splatter.wps.com/cgi-bin/mailman/listinfo/amc-list