Been lurking for quite some time and decided it's time to post.

I searched through many posts regarding vibration issues, but none of them seem tomatch the problem I'm having. I've got a 2005 QC AWD w/4.7 engine and about 23,000 miles. No suspension, tire, or wheel mods.

Over the past couple months I've had a strange vibration that seems to be coming from the rear end of the truck that feels like the rear wheels aren't catching up with the front. I could be driving along thesmoothest stretch of road (which is rare in western PA) and it will feel like I'm driving on a washboard. The problem will last for a while, but then will go away. It seems like the problem occurs when the truck has sat overnight, but I can't prove that one yet.The vibration gets worsewith higher speeds.

I took it to thedealership, and of course I got the "couldn'tduplicate the problem so there's nothing we can do about it" speech and told to bring it back when the vibration was happening. Problem is, the vibration never seems to happen when I'm near the dealership.

Do any one of you have any ideas about what might be going wrong? Could this be the rear brake/axle problem that others have had?

Thanks much in advance for your help!

 

might be time too change out the fluid. then you could really look at the carrier unit to see if it is loosing a c-clip or snap ring

 

I hate to sound stupid, but I'm not sure which fluid you're suggesting that I change. I checked the trans fluid and it looked clean...

 

I think he's referring to the rear differential fluid.

 

yeah i mean that could be it but it sounds like something has come loose or is rattling around in the rear end...I've never really heard about any problems like that coming from the rear end from not changing the fluids at 23,000. I mean its supposed to be done at 15K....but i mean still yeah....never heard of that.

 

Just to rule out a couple of possibilities, Have your tires ballanced and rotated. If the vibration feels like it moved to the front, you could have a belt broke. Make sure they clean the back of the rims.
The corrosion where the rim mounts to the roter will sometimes cause vibrations. Usually in the steering wheel. But still possible.
Just a thought. Hope it helps.
WvChamp

 

It wouldn't be the tires if it is intermittent, I would try changing the fluid in both axles, while you are at it switch over to amsoil...

 

heh, Have fun with the front diff...

 

yeah today i just switched to AMSOIL all new fluids and to be honest my truck feels like its running alot smoother!!! so yeah...i was a mobil 1 fan and now I think i'm gonna stick with AMSOIL and i like that warranty they have with that oil! "if it causes any problems and the fluid was the source of the problem they pay for it all! pretty sweet!

 

How long did that front diff take you to switch the fluids?