I got one I hope you guys can help with. My 03 4x4 QC has had a vibration from the rear for a while. I have had it checked and know one seems to be able to tell my anything new. It seems to be at its worst at highway speeds regardless of road conditions or wether I am pulling my boat or not, the boat does mute it a little but it is still evident. It stays in the rear whether I rotate the tires or what, its never in the steering wheel only in your feet or seat of your pants. Here is some of what I have thrown at this so far - new wheels and tires, new shocks, new axles bearings and seals, new rotors and pads, new drive shaft and u-joints, and cracked open the diff and checked it out nothing obvious other than a busted clip that didn't appear to do too much damage.
I am about to give up on this thing and get rid of it. I do 75% of my driving on the freeway and it is driving me nuts. Oh yeah it started at about 75000 miles and I am at 125000 now if that helps any.

Thanks to anyone who might have an idea, and let me know if you have had a similar issue.

 

We have been experiencing the same unknown problem with my wifes Mustang. Got new tires, etc etc. Took it in for alignment (which won't fix vibration) and found that the car had been lowered an inch with Eibach Springs (bought used at 10K miles). Discovered that the camber was way off causing the vibes. So, now we gotta get a camber kit to fix that. Have you changed springs or anything? Her car would only vibrate at 60mph, not before.

Just a thought, may want to get it checked out.

 

I bought the truck new, I haven't made any mods to the suspension. When I bought new wheels I even bought exact same size 20s so as to not add something diferent to the mix.

Thanks for trying though.

 

I've got a similar issue. My '05 hits a harmonic right at 40, then smooths out around 43-44. Then hits another around 66 and smooths out by 70 (all mph's). I've got 17" moto metals and 33's. It's done this ever since I bought it with 23k miles and it's got 66k miles on it now. I've had two different sets of tires on it and it doesn't make a difference. Rotate the tires, no difference. I've even switched out wheels and tires with my buddies '03 off road package 17" factory wheel and tires, no difference. Can't find the problem. I've taken it to at least 7 places and they all tell me it's the "oversize tires". I have no idea and I've just learn to deal with it since I don't drive it everyday anymore; but I feel for you, I used mine as a DD for two years and it drove me crazy!! Let us know if you find the prob.

Good Luck, there's a lot of knowledge on this forum and there will be a lot of good suggestions, don't get too frustrated and maybe you'll find it and smooth out that ride!

 

I no what you mean about the "they say its the oversized tires" deal. I have had more than my fair share of supposed knowlegable people tell me that. It didn't do it for the first 70K miles with 20s why would it do it now with 20s has always been my response.

thanks for the encouragement hemiauburn

 

yeah, that really gets under my skin when some hotshot yahoo with a "dodge oil changing degree" tries to tell me that the truck will never ride the same with those "oversize off-road tires" on it. I know they are a little larger than normal, but not too much. They are heavier and MAYBE and inch taller than the factories, but I've got 38's on my older truck and it rides like a dream.
There's a lot of good mechanics out there, but there are just as many idiots trying to blow smoke up your @ss just because they work at a dealership and get a discount on new vehicles.

 

Did you have the transmission mounts checked? I had a an old truck that used to do what you are describing and it was a mount. Other than that you've pretty much covered all the bases

 

No I havn't checked the tranny mounts. That one I didn't think about. I'll check that out and let you know what I see.

Thanks dublduty

 

I as well am having issues with a vibration.. It only occurs during 50-60 mph but I also am hearing metal pieces clanking around only when the tires are rotating.. Nothing with the truck is still.. They seem to think something might be going on with my drive shaft or u-joints... I then brought up your issue to them and they mentioned that maybe its your pinion angle.. Maybe you had that checked when you replaced the drive shaft but just trying to help you out..

 

No noises with me just the shakes. About the pinion angle? Dude I am lost there. I try to do everything I can myself cause I don't trust the nuckle heads you find now adays, but that sounds like it is beyond me.

thanks flex