Originally Posted by whiterhino
I would go 3.0 or 3.8. Because of your 5.3, probably 3.8.
I'm running a 6.0/TH350/3.8 & 4.88's with 40's. I've never felt like I need a lower gear. More HP at times yes, but not a lower gear. If you feel like you have all the umph you want for bumping on rocks & logs, the next thing you want is to be able to generate wheel speed immediately. A lower gear generates RPM, but not wheel speed.
Yes, your NP231 is 2.71:1. When I had my NP231, 2nd gear low range was my strong gear. Now with the 3.8, my strong gear has moved to 3rd gear low range. It's great because all I do is shift it into D and let the trans do all the thinking. Before, I had to intentionally pull it down into 2nd.
Mine is in a YJ with a body lift so I can't comment on the fit. But Tab has an Atlas in a TJ and I don't think he had to do anything special.
mine is a 6.0/th350/3.8 atlas/5.38s and 42s.
only thing I would change would be an OD trans. I would like to have another gear when in low range so it would reach higher speeds instead of switching back to hi-range. it still moves out in 3rd/low range, but want another gear.