I have a '96 JGC Limited with the AWD Quadra Trac, and it is obviously not engaging the front wheels. Any known issues with this that I can look into before taking it to a mechanic?

Sounds like your chain in the T-case is broke, with the front wheels off the ground, can you turn the driveshaft to the front axle easily? If so, I would look at rreplacing the T-case. When you turn the DS your front wheels should rotate too. If not look at your differantial. What happened that you noticed the front-end not working?

I parked the rear axel on ice, the front axel on dry, dusty ashpalt and peeled out consistantly with the rear tires (in both 4 all-time and 4 lo). Also gunned the vehicle into a slide, turned into the slide and accelerated, but the slide only worsened. Doesn't feel like the front end is doing anything at all. There is no noise, etc. coming from the front end either.

Ok, that is one way of "checking" the system. I wouldn't recommend dong it too much. There is something wrong, don't need to worsen it. Your going to have to get under the GC with the front off the ground, and check things out like I stated before. You need to isolate the problem eith er to the front axle or the tranfer case. On the 94 GC I worked on, I found that it was next to impossible to turn the front tires when the rear tires were on the ground, and the front off. It sounds like maybe your T-case is an issue here, but you need to isolate the problem. Front axle or T-case.

Last night I dropped it back into 4-LO and there was an audible thunk (good, solid sound). Drove it around a little (all pavement unfortunatly) and it felt like the front end was working, I could feel it in the steeering. So I dropped it back into 4-All Time and it still felt stiff in the steering, like it was still pulling, but I couldn't be sure.

So my question is this: I have 3 settings on the Transfer case (4-All Time, N, 4-LO). My understanding was that in All-Time it was always running the front end, not just engaging it when it felt slippage. Is this not the case? Does it only engage the front axel when encountering slippage?

< Sorry, looked on the forums again and I think I understand how the 249 T-Case operates, so I'm just not sure if it is failing to make the engage and then failing to disengage...I'm going to completely swap the fluid out, and while I'm doing that I will jack up the front and see if the front driveshaft spins freely with the rear wheels on the dirt. >

sounds like a good time to drop in a 231 or 242 tcase

jdennis, you are right 4WD all time, you are always in 4WD but you only have 30% power to the front wheels and 70% to the back wheels, then when slip is felt in the back wheels the VC lock-up supplying equal power to each axle.

well it sounded like the chain was broke, but since you said you feel the power to the front wheels now, then it sounds like the VC and/or gear (can't think of the actual name) is slipping apart.
Have you had any Transfer Case work done?

Update:

Ok, the 4 Hi does nothing, but when it is put into 4 Lo that does seem to lock in. However, sometimes it will fight you (grind) or pop back up to Neutral on the transfer case.

Not sure, but from what I'm hearing it sounds like it is the VC.

How did it turn out?

I have a similar issue:

I just bought a '94 Jeep Grand Cherokee (Limited) 5.2l engine (126k). I bought it with a bad transmission (car could only be moved switching into 4 wheel Low). I had a friend of mine in WV install a transmission with 96k on it - said it was a real good looking unit. I drove back last night without incident - until I came to the first red light of the journey - the replacement transmission has gone the same route. Symptoms: Won't move off of the line from parked (appears to be in neutral). Putting Jeep in 4 Wheel Low will get it to move, though very slowly and underpowered for the RPM - this last for about 30 seconds and then it will kick up a gear and will move OK. Reverse is not a problem.

I tried disconnecting the battery in case the computer/sensors threw it into some kind of limp mode - no joy.

Jdennis - i do not believe your problem to be the VC, the VC douldn't stop it from going into and out of gear, i think your shift linkage is out of adjustment.

Jdennis - i do not believe your problem to be the VC, the VC douldn't stop it from going into and out of gear, i think your shift linkage is out of adjustment.

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