Grinding Noise from T-Case? Front?

I have a 2001 XJ, 3" lift, T-case drop, 105K miles. Recently I heard a noise that sounds like a grinding up front. I didn't want to mess with it, so I took it in and had it checked, they said the front end bearings etc. were fine, that it sounded like the T-case. They tore into the T-case, found a bearing, fixed it, put it back together and still has the noise. They tell me they have no idea what is wrong, and it may just be that the T-case has too many miles and will just keep grinding (if that is even what it is, as I thought it was from the front left)? I have been through some deep water lately, but changed front and rear diff, just to make sure. I know you guys know your stuff. Any ideas??

Thanks.

Brian

It might be your front driveshaft, and its easy enough to find out if it is just pull your front drive shaft

I think we have the same exact problem. I replaced wheel bearings and ujoints on the front and it's still there. I also disconnected my front drive shaft and it was still there. It's pretty much right under my feet. The noise gets faster as I drive faster and slows down when I slow down. If you ever figure it out PLEASE let me know what it was. Thanks!

I will check the driveshaft, but the sound wasn't coming from there I don't think. I jacked it up and tried to recreate the noise by having my buddy turn the drive, etc. At the Dodge 5 star service, they calculated the driveshaft angles for me and are going to call Chrysler Tech support and see if they can help. They said the driveline angles were 0 degrees, which means nothing to me. I don't have a SYE, maybe they will tell me I need one or will need to shim my axles?? I'll keep you posted.

Josh - Do you have a SYE?

Pinion seal or maybe even the ball joints?

XJJazz said:

Josh - Do you have a SYE?

Click to expand...

yep

They are telling me that the T-case is bad. And that as it gets worn out it gets louder. I can find a used one to stick in it, but can I run this one till it dies? Should I go ahead and bite the bullet, or is there somthing else I am missing.

When I bought my 2001 XJ (with 44,000 miles), it had a speed dependent noise in the front end that I thought was the transfer case. I took case apart and found nothing wrong. After doing of lot of trouble shooting, I finally found that one of the front differential carrier bearings had gone south (the outer race was toasted). I replaced all the bearings and reset the R&P and it is now noise free. To pinpoint the noise, I first removed the front driveshaft (no change) and then both of the front axle shafts. Removing the front axleshafts stopped the differential front spinning and this eliminated the noise, isolating it to the front differential. I used a couple of large, one-inch bolts and nuts to clamp the wheel bearings together, prevent them from falling apart during the road test.
BTW, I had two recommended Jeep shops look at it and they were unable to pinpoint the noise, so many times you are on your own to track these problems down. Both of the shops wanted to tear the transfer case down but I stopped them, knowing that it wasn't the cause.

I'd lean towards the front differential....if the pinion shaft bearings are bad that can mean that the backlash on the ring/pinion is not in spec and will cause this noise. This happened to me and before I figured out what the problem was, the grinding noise turned to a whine/howling noise that rises and falls with the speed of the car. At that point I could hear that the noise was gear related and I didn't have the front driveshaft on at the time but it was clearly coming from up front. Interesting note- when I removed the front driveshaft, the noise got a little quieter. My theory is that the vibrations coming out of the front pumpkin were being conveyed up the driveshaft and into the t-case just below my right knee...once the shaft was removed the vibes were harder to hear and seemed further up front.