DTune1981

Due to a t case failure,I installed a new SYE T case last year, on a stock xj, only because I wanted it a bit stronger than OEM. The back end is saging, and its almost time for a set of new tires. My question is, should I do a 3" lift, with 31-10.50s with the stock 16" factory alloy wheels? my goal is to solve the sag in the rear, make it look a bit better, and a little beter in snow, and light mud. I dont do much off roading, and it is my DD. It is a 2001 model and in very good condition, with only 80 K. I have looked at the RC 3' series II with rear springs. would I need to do anything else? Mainly for road use. Thanks