ok so since the winter is coming in illinois i want to use my four wheel drive the only problem is idk if it works. I got the jeep about 3 months ago and the people i bought it from said it did (stupid me never tried it). i read that your t case could blow or that u could be stuck in 4x4 and it cost alot to repair so im kinda scared to try it. whats the worst that could happen if it doesnt work? its a 91 laredo with 162k on it

 

The biggest issue you could have is the vacuum disconnect on the front axle not working, if your Jeep is equipped with it. 91 was the last year for the vac disco front axle and not all XJs had it. The 2 easiest ways to tell are by looking for the shift motor housing on the back side of the axle housing on the passenger side, or if you know which transfer case you have. The NP231 tcase, identified by a 2H - 4H - N - 4L shift pattern, or the NP242, identified by a 2wd - 4 part time - 4 full time - N - 4 Lo shift pattern. The NP231 will be a vac diso front axle and the NP242 will not. The problem with the vac disco axle is they are prone to vacuum leaks, broken vacuum lines, and faulty shift motors that engage the axle shaft on the axle housing.

 

so if i do try to put it in for wheel drive and there is something wrong will it get stuck or will i be able to just drive it as a 2wd vehicle

 

It is hard to say what could happen if there is a problem until we know what tcase you have and try to diagnose what is at fault. Check to see which tcase you have first.

If you have the vac disco front axle and it is faulty, nothing will happen at all. The vac disco axles have a 2 piece passenger side axle shaft that is locked together by a collar. The collar is slide into place by a shift fork operated by vacuum when you engage the transfer case. If there are vacuum leaks, broken lines, or a defective shift motor the collar will not slide over and you will basically still be in 2wd. The non disconnect axle, with the NP242 tcase, has a one piece axle shaft on the pass side.

 

ok ill go check right now

 

its 2wd - 4 part time - 4 full time - N - 4 Lo shift pattern

but look at this

 

So you have the NP242 so no worries about a faulty vacuum disconnect. The only thing I can say for now is to put it in 4 wheel drive and try it out. The 242 is a reliable tcase and usually doesn't have many issues unless neglected or severly abused. It does appear in the photo the the inspection cover on the transmission bell housing is missing. While this is not a huge problem, it should be replaced to prevent rocks or road debris from getting in there. A nice rock at highway speeds can do some nasty damage to the flexplate and torque convertor. You should be able pick one up at the local junkyard for just a few bucks.

 

thanks man your amazing

 

just remember, when you try out your np242, not to put it in 4wd in your driveway then turn out of the driveway. this is what i did when i first got mine. part time locks the front and rear differentials together. full time engages the center diff. full time is ment for road driving, and part time is only for slippery and loose offroad driving or in deep snow. if it get stuck in part time and you turn sharp, you may hear a loud pop noise. i did that the first week i got mine, and it scared the **** outta me. just make sure its in full time before you drive on the road.

 

The definitive way to check of the 4WD works is to engage the transfer case, drive it a few feet and wait for the light to go on if it will. Turn off the engine, put it in park and jack one front wheel off the ground about an inch. If you can turn the tire, it does not work. If the tire will not rotate, it works.