Hey yall, I changed my oil today. Saw I had a jug of rotella-t 30 weight and thought I'd use that and top of the rest w/ walmart's supertech 10w30. Turns out I've already packed up the supertech (getting ready to move), but I found some Mobile-1 10w30. I bought it a few years ago for a turbocharged car and never used it. Not sure what I got the rotella for, maybe one of my pickups or a lawn mower. So I ended up with about half rotella and half mobile-1. I don't expect any problems but maybe yall know better. The jeep's a 99 with 147k, never used synthetic, and it keeps the outside of the engine well oiled. Uses a quart every 10k.