New guy here. I have read a lot of the oil analysis on this site, very interesting and informative info. Any one have an opinion of Castrol GTX vs. Chevron Supreme in 5w30? I know the Checron is a group II+ base, unsure about the base oil for Castrol. I have a 2002 Ford Ranger with 3.0 and total of 13,000 miles, I stick to 4K change intervals. Both oils seem to do well in UOA, any takers? Thanks.