Originally Posted By: demarpaint
I have Edge 0W20 locked and loaded for my Jeep.
I know that the 3.8 calls for 5W20, but personally I wouldn't run a 20wt in this vehicle. They run hot, especially if you wheel. The tranny cooling system too. I've seen a couple of smoked tranny's on the trail. One time on a mild trail system, we were all playing on this one small rock/hill climb. After a few attempts, smoke started coming out from under my friend's Jeep. We couldn't find a leak! The tranny was so hot, it vaporized the fluid. His mechanical water temp gauge on the engine read about 230*F!!!. His engine sounded very tingy and he was running Valv WB 5W20.
I don't think Jeep was thinking about overall durability when they slapped the 5W20 cap on this vehicle. This is from a guy who runs 5W20 in a Ford tow rig. IMO, the cooling systems are lacking.
Anyway, not trying to rain on your parade, just trying to help. My wife wants a JK 4 door, and the first thing I'd do is install the biggest tranny cooler I could find and dig into my stash of Q-HP 5W30 or Q-TP 10W30 for summer. It's not like you're going to pick up any MPG's driving a brick with wheels.
