If you mean XJ.....
6cyl was good, and w 3.55 gears could do 31s without too much power loss.
Most had D35s though. Later 8.25 rear ends supposed to be good.
Rear seal leaks common so those aint too rusty LOL.
Most here (Indiana) have the rockers gone.
Steering box area needs reinforced, rear springs sag, so replace w better. Blind pockets so can be a PITA. Use impact tools and even then may have to weld up a new pocket if the nutsert breaks loose.
231 better than 242 T case. But the 242 allows 4wd on pavement (supposedly). I didn't run mine like that and still blew em up. But they had a lot of miles on em when they let go.
Crank sensors can be a PITA, harness gets cooked......so maybe harness or sensor. Not too expensive but even if you replace a crank sensor, might have to do that more than once.
Had a couple of XJ and wheeled em. Broke everything they said would break, and I'm not hardcore.
Fun rigs, good lookin.........wish they still made em.
Theyre sporty. Going to a ZJ (Grand Cherokee ) was like driving a queen size mattress.
Sporty feel of XJ totally missing.
But the ZJ ride was more comfy. And w 5.2L engine was kinda nice (both of mine had 3.73 gears). Both XJ were 3.55.
Getting old, back problems........Z J w 2" budget boost and 31's about perfect.
But like the Cherokees.............just rotted away around here ('98 last yr of ZJ).
