Blu you're so correct. When I went and test drove the vehicle; it rolled down his driveway when I returned and placed it in park!! The AT would sometimes have to be put in N to get the Jeep started. Went and got the linkage adjusted to remedy the problem... Glad you told me how it affected the TC and the tranny when someone takes the shaft out.


Put some grease on it - it DID improve but still vibrates some.

-My alignment is off
- rear brake pad has a heat crack
- freakin motor mounts are broke
- this is my first time ever driving/owning a ZJ... Just got the front driveshaft put it.

Since my brake pad has a small crack, alignment off, bad engine mounts- I'm thinking the problem is a result of all three things. I think now with the front shaft on; everything is working a little harder underneath the jeep- thus allowing me to feel the bad pad and bad alignment much more. I took it on the freeway this morning to feel highway speeds.... Smooth as expected with AWD.

I think I got this solved (thanks to everyones help). I'll let you know what it is.

 

Let us know what you find. We're here to try and help, if we can.

 

http://jniolon.clubfte.com/driveline...nephasing.htmlis the shaft phased right its hard to tell by the pics

 

thanks for the link, That explained a lot and allowed me to verify it was phased correct. I also went out and bought a haynes repair manual. My wife thinks I'm a nerd because I'm sitting here reading it like a novel while we watch tv. (she has the remote what do you expect me to do )

bad angle of pic - but yes the shaft is phased correct. And also, it's a factory shaft from what I can tell so I'm hoping I'm correct when I say the angle is also good. (but when I look at it from a horizontal view it looks like a straight arrow, and I cannot tell if the center lines are parallel)

So today I called the shop who threw the drive shaft in for me. I explained the issue, and how it happened the second I left the shop and hit the first stop sign. I met the tech, and we hopped in the jeep together.. He instantly felt something and said he could feel it under his feet on the passenger side. He said he didn't think it was the rotors, and maybe it was a U-joint or driveshaft or transfer case issue. He also double checked his work and said it was bolted on good.

I asked the tech what he thought I should do next, he said "heck, if it didn't do it before the shaft was in I would just take off and leave it off"... wrong answer buddy - I was schooled on CF!! This will ruin my TC and that's kinda what I'm afraid of. I am taking it to a reputable drive shaft repair shop in town and will see if it is balanced/bent or whatever. I'll start at the shaft, then U joints, bearings etc...

Just so crazy it happens the second I get the drive shaft on. Unbalanced drive shaft maybe?? Or perhaps my transfer case got beat up by the previous owner. I'll know more tomorrow. Thanks guys

 

ill bet the shaft is out of balance

 

heres one you can look at on the pchttp://www.jeep4x4center.com/knowled...ex.htm#service

 

UPDATE:

Shoot, I was hoping the shaft was the issue (easy fix) but I guess it wasn't. I brought the ZJ in to a drive shaft/U joint shop - and I had them replace the factory Ujoints. The rubber inside (boot I think) of the collar was so dried and cracked.. The grease wasn't staying in.

I was hoping that was the issue, but still same exact issue. The jeep does feel a lot better when driving, but still.... braking at 30MPH and 20MPH I get the same heavy vibration under the drivers feet - and it can be felt on the passenger floor as well.

the joints still needed to be replaced, so I'm glad I have that taken care of. I just really was hoping it was the shaft or u joints. Tomorrow I will get the brake rotors checked - this issue only happens when braking!! AHHHH. I wonder if the previous owner did in fact ruin the transfer case? I dunno, it's crazy this issue happens only once the front drive shaft was put back on the ZJ. Surely is a great learning tool for me, I'm staying positive and just looking at it like on the job training.

My ABS and Air Bag light has been on since the first day I bought the jeep. HMMMMM???? Well, thanks again everyone for the suggestions and links. Even if it doesn't solve my problem, its literally helping me learn a lot.

 

Hmmm. Not the drive shaft, not the brakes, everywhere I've taken the Jeep; they've been stumped. In the morning I will get the codes read... Maybe that will tell me something.

 

front bearing in tc case see if the shaft wiggles around there

 

The NP249 has always been a problem because of the viscus coupling. A little trick some people do when selling one of these Jeeps is remove the front drive shaft if the coupling has gone bad.

Pulling that front drive shaft will completely mask the issue to an unsuspecting buyer. What you may be feeling is binding between the front and rear axles due to a lack of slip within the VC.

I'm pretty convinced that this is the case with your ZJ. When the VC goes it becomes the equivalent to driving a part time 4wd vehicle all the time. Just about everyone knows that if your in part time 4wd that you WILL damage either both diffs, yoks, T-Case itself, and especially the CV Joints. CV's will probably be the first to go... Have you checked them to make sure they are in good condition?

 

Great feedback everyone. Yes you seem to be right on point FAlfani, I think this seller hustled me pretty good. I still love this ZJ though. my passenger side CV joint was recently replaced. I've been sitting here form the last hour or so researching VC and failures its seems like this is a serious problem. Now the front drive shaft is in in really feels like its in 4wd all the time. Since I have the 249 isn't it supposed to feel like this or does this mean it is stuck in 4wd? I can still shift into 4lo and feel it kick in just fine. But now I think I might smell the burning scent people talk of. Oh and its also pulled to the right. Even after the alignment yesterday it still pulls just the same to the right.

Also though, I need to point something out that I totally forgot to include in the original posts. This may not even be of importance but all the info helps I'm sure:

As I said I had NO issue at all with vibration while braking BEFORE I had the front drive shaft put back in. But this is the part I forgot to mention. I actually had the CV joint replaced the same time I had the front drive shaft put in. So the vibration started the same time I had the CV joint replaced. Is there any possibility the didn't install it correctly? Right when I felt the vibration I drove back to the same shop and they re-checked their work. There's a chance they only checked the drive shaft bolts and not check the cv axle.

Also I'm attaching a receipt of the work a different garage did 2 days later. Since I was worried the front drive line was messed up I had them check everything out. I also know ALL fluids are dirty - transfer case, differential, brake, transmission - they all need to be replaced which I will do so right away.

I can shift from 4 hi to 4 lo and everything is working ok. In 4 lo I can still make the same issue happen at the same speeds when braking. (vibrating at 30 and 20 MPH, also I can feel a vibration when driving at these speeds, but the vibration is very very light and can only be felt by someone who "knows" the ride of the jeep. It really is there but it is a slight vibration.

- went to a cv axle repair shop - got a new cv axle (gold duralast from autozone) - immediately I have the "issue" Go back and they re-check all their work and say its probably a bad driveshaft, and I should just take it back out. (no I've learned this is VERY bad for my 249)

- went to a driveshaft/ujoint garage - and attached is the receipt of the work they did. They say its probably something with the ABS (my abs and air bag lights have been on since purchase 3 weeks ago)

- went to midas and got a free 55 point brake evaluation and alignment done. Said rear pads need replacement and front drums re-surfaced. Then they said to go to the dealership and get the codes read from the DRB scanner. I looked like a moron going into the dealership today asking to get my codes scanned... with no check engine lights on!!

I am going to buy some tools and replace all the fluids. I'm going to do some more research. Thanks again everyone, sorry for such a long post. Everyone has been a great help!

 

s***, it is my VC isn't it?? I just went outside and did very slow figure 8's with the wheels turned to the max. right and left they screeched/bounced very bad. It felt like a tug-o-war going on. This is my first all wheel drive vehicle and I was thinking some bouncing might be normal for a transfer case that had 4wd all the time. When the mechanic got in the jeep with me he said it was normal, but I'm thinking it's not normal at all. This is the same mechanic who told me to just take the drive shaft back out and drive without it.

BTW, the seller told me he took it off for better gas mileage and that is was very common for jeepers to do so. (he knew I was a noob). He said no leaks ( I had the replace the water pump 2 days later) He kept going off on how his son was going on a church mission and needed money for his trip. He also said it was a rebuilt engine. I bet that was a lie too. Oh well hope the kid is actually doing something productive

 

Yes, it sounds like the VC is toast. It would be cheaper to get a used t-case and install it than to have yours rebuilt.

 

this sounds like my girlfriends grand cherokee...bought it and front driveshaft had apparently never been used: in bag in back of jeep...she gets a weird grinding and vibrate when barely touching the throttle and when jeep is decelerating...i had wanted to take front shaft out to determine if it was u joints but after reading this thread will try not to destroy the tc anymore... i am righ here with you...think her issues is about the same as yours and wanting to know what to try from here...find a used transfer case is my guess?

 

Good guess. Cheapest fix too.