Whatever one is in my 02. I like it. Never had a problem "knock on wood"
I believe if you go 42rle you will have to replace the ecu.MarkNog said:I like the auto 42rle in my 04 tj becuase when you put the pedal to the floor, it won't shift out of that gear until you let off a little of when your pushing 5k rpms. I have 31s with only 3.73 gears but when you hit anything over 3k rpms you can really feel the power!