I had this question asked of me and thought maybe some of you have run into this. I told the guy without more info or looking at it I don't know....

"A buddy of my just bought a used '94 Jeep Grand Cherokee for his wife to tote junior around in. He called me the other day wanting to know if I knew the answer to a problem he is having with it. I had to throw my hands up for not knowing enough about the "newer" Jeep stuff. Here's what's up:

When making slow speed tight turns, he is hearing a "chirpping" noise coming from the rear-end. He thought that maybe the LSD might need the friction additive. So he bought gear lube and additive, pulled the cover and it's got an open diff. He checked end-play on the axle shafts- nothing excessive. So, the question is; this has the "all-wheel-drive", neutral, 4-low lock buttons on the dash. Is there some type of viscus-coupling devise in this T-case or is a "mechanical" type of power spliter? He has not been able to locate a service manual for it yet to investigate what's in the T-case, but he still does not want to break something before he can get a manual.

Ever heard of anything like this before with the Grand Cherokee's? Or any idea's on if the T-case may be the cause of the noise or binding on the driveline? Any help would be greatly appreciated by him. "

Anyone have any ideas?

Chrysler no longer sells the technician manuals. I got one for my Dodge thru my Dad (an employee) in 94 but couldn't get one for the wifes 98 ZJ. The Jeep dealer can give you the suppliers phone number that they buy them from. I had it and lost it. If your local dealer can't get it for you then get back to me and I'll get it for you here. I'll need one soon seeing that I'll inherit the ZJ from my wife next month.

Can't say I know a damn thing about the all wheel drive:confused: in that Cherokee but the Subaru's use an all wheel drive setup and it differentiates at the t-case so as to be friendly on the street and not bindup. If the problem was there I would think the rearend would still differentiate around corners even if the T-case didn't. Just like an open diff I heard that setup sends power to the wheels that are slipping. Just what I heard. I know this isn't crap for an answer but maybe a something to think about. But the sound your describing sounds like a locker. Pull the rearend off the ground and check to see if the axle is differentiating with a buddy holding the other wheel.

Originally posted by lostone65



Anyone have any ideas?

My wifes does that at slow speeds. My 1 ton dodge does that at slow speeds too ;)

The '94 ZJ uses the NP-249 all-time T-case. This case splits power using a viscous coupling. When the VC starts to go bad, it begins to lock the front and rear shafts together (part time 4wd). These symtoms will get worse and worse as the VC gets more and more worn. I replaced my 249 at ~70k miles dues to these symptoms appearing, and wanting a "real" t-case. Pre -'97 model of the 249 don't even lock the shafts together in 4-lo......what a crock!