Hi all,
I have searched many of the vibration threads and haven't found an answer to my question. So I'm beating a dead horse here with this topic.

Let me first say that I am not mechanically inclined like many of you. I can basically put gas in and on a good day change my winshield wipers.

On to the problem,
I have a 2007 GC with roughly 85k miles on it. Thank God never had any major problems. The other day I was driving and out of the blue there was a vibrating noise coming from underneath the middle console (a little more towards the backseat). It almost sounded like something was lodged in the drivetrain. But the funny thing is that besides the noise, the Jeep seemed to be running normally. When I would come off the gas the noise would go away. On the way home, we hit a small bump and the noise totally went away. That night I took it for a ride, I went out for about 45 minutes, on the highway, stop and go, smooth roads, bumpy roads etc.. The Jeep ran fine. I chalked it up to a piece of asphalt (or something else)coming up and getting lodged somewhere.

Sure enough a week later, the same thing happened with same symptoms. The next morning my wife went to bring it to a garage and of course the noise went away. The mechanic gave it a quick glance and said everything seemed to be ok and it would be tough to figure it out without the noise being present or putting it up on lift which he didn't have time to do that day. He said that if it was something major/catastrophic the Jeep would not continue to run. He said to try bringing it in the next time it happened.

Personally I hate the idea of my family driving the Jeep around with this impending issue likely to pop up at any time. Does anyone have an idea on what this could be? I am hoping it is a minor issue based on the Jeep still running, but I also know that minor issues could turn in to major disaster fairly quickly if they aren't taken care of.

Any help would be greatly appreciated.

Thanks

 

One thing you CAN check, if you're willing to crawl under it, is to check the rear drive shaft for a worn out front bearing in the transfer case. You should push up and down forcefully on the front universal yoke and see if there is any looseness where the shaft goes into the transfer case. If the bearing or splines are worn, it can be thrown off center occasionally and run straight most of the time. This will most of the time cause a fluid leak, so this may not be the case. This bearing is brass or bronze where the slip yoke goes into the transfer case.

 

Thanks for the input Dave. Just got the phone call, it actually has to do with the emergency brake cable wearing and getting loose. It's pretty fustrating, from what I hear it's a $40 part. But because of where it is and the labor involved, it will set me back about $700. I'm pretty annoyed about the entire situation and am getting nowhere fighting with Jeep as this something not covered under the powertrain warranty.