im looking at a 1991 XJ on craigslist and am very mechanically inclined. Question 1. Are all NP231's internals interchangable. I have a 94 chevy PU with an extra Tcase and think i may need a few parts the next question is what are common driveline issues with a 1991 XJ. Heres a quote from the listing of the jeep im looking at (not my wording or grammer)

"i have a 1991 jeep thats wight with tan leather atuo lock and windows 4x4 stright 6 4.0 with 170,000 mials engin has hade resent tune up as far as oil change plugs plug wiars raidiator flush all belts not sure whats wrong with it will not move when i put it in gear i dont thank its the trainsmittion i thank its the transfercase or drive shaft easy fix for someone who knows about 4x4's"

Im going to look at it in the am and decide, again im probably gonna get it but wanna know some tips to look at upon initial inspection of the no drive issue. Thanks in advance and sorry for the long post.

 

Ha thats hilarious! You are gonna have to look at it. There is no way you can take anyone's word who writes like that. Most of the 231 parts swap right over. Make sure the jeep has the 231 when you look at it. There is a tag on the back of the t-case. XJ drive trains are pretty bullet proof. My bet is the shifter linkage is busted. Bring a Phillips head screwdriver and a flathead. Take the shifter **** off, you gotta just pull it off straight up. Some get stuck on there pretty good so dont get scared if its giving you trouble. Then just pry up the shifter cover. I cant remember if they are screwed on or not hence the phillips. Check the linkage, i have seen a few break, you might have to bring a buddy to sit under the car and make sure the tranny shifts into gear when you move the shifter. I hope thats just the problem.

Good Luck!
-Mike

 

thanks mike, your answer is the one im looking for. Hope thats all it is, I just cant tell from the listing and the guy selling dosent know what it could be, he suggest a drive shaft but im kinda new to the XJ but like any other vehicle on the road you should be able to look at both shafts in about 5 seconds to determine if they are connected.
Even if he managed to break an axle shaft it should move in 4WD. Thanks for the reply. I"ll post my findings, and any other tips are welcome.

 

its definately the trans or torque converter. You can hear and feel the dngine changing RPM when you select a gear. It does absolutly nothing in gear and there is fluid all over the bottom. My old truck did the same thing after I lost all my fluid on the interstate, slipped until it wouldn't move anymore.

By the way I found a trans w/converter out of a 83K mile XJ from the salvage yard, with a 6month warranty.

 

Haha. Wow. Someone didn't get far in school.