Hi Guys

So I have a question that has been in the running for a bout 5 weeks now! And since my mechanic can't find what wrong with my truck, I have turned to you guys for some suggestions.

I have a 2002 2500HD 4x4 with 189 000KM on it, its totally stock.

I took it in for a tire balance and rotation about 6 weeks ago as the truck was starting to get a shimmy. The guy at the tire shop told me that the trucks tires were Cupping, and that I would need new ones before winter came.

Truck still vibrated down the road at about 72-79KM/H, so, since this truck is KNOWN to spit U-joints I took it to my mechanic to get that done.

Took it to him and he couldn't find anything wrong except the tires, replaced all 4 of them with Nexen stock size 16's. The vibration didnt go away.

Took the truck back to him to look more into the U-joint and sure enough it was TOTALLY seized, replaced that with a heavy duty one that has a grease nipple (truck already had an after market so I do know that it has to be greased all the time) and we also felt that since I got new tires and the truck has never had an aliment I should do that too. Vibration went away for about a week and then CAME THE EFF BACK!!! So,
took it back Last Thursday, the only thing the could come up with was my rear shock, replaced them, truck ran great!

Drove it from Toronto Ontario to Mentor Ohio (6 hours) with it LOADED no trailer, just loaded with 5 people that all weight about 200lbs, and then the bed full of sh*t. Drove like it was new.

On the way home I had 6 boat stands in the back, and it still drove great.

When I took everything outta the truck, the EFFING vibration was BACK!!!

Took it back my Brad Wed night, and he drove it for a good time, took OFF my tires and rims and put another set of 8 bolt on (same size and everything) and it drove the same.

The problem is, you cannot recreate this vibration on the hoist!

WHAT in god name is wrong with my truck!!!!!! EVERYTHING has been checked, axle, breaks, diff, the tranny, drive shaft! EVERYTHING

now the only thing I could find about my vibration is that it might be "Frame Beaming"? if so, I just have to weight it? Has anyone had this problem before? I'd love some insight, either that, or do you know anyone that wants to set my truck on fire? its fully insured!? :D

Thanks for your help guys!

My thoughts: Find an Frame & Axle shop in your area, take it there to see if everything is still true and square, as well as front end and rear axle alignment. Look for a "Six States Distributors" shop in your area, they did wonders for balancing a driveline on our '86 C2500 that kept chewing up tailshaft bushings.

I'm just offering advice from my experience, the afore mentioned C2500 was a camper special that someone put way to heavy (pin weight) of a 5er in the bed and tweaked the frame. Didn't reaize it after owning it for a couple years, took it to a shop called Beeline Frame & Axle in Moses Lake, WA; had them align the frontend and straighten everything else out. Few years ago it developed a leak in the tailshaft of the transmission, no really noticeable vibration though. Replace the seal, all was good for a while. Started leaking again, slight vibration. Replaced tailshaft bushing and seal, everything was golden. 6 months later, same thing; long story short: a weight had gotten knocked off the driveshaft and it was now out of balance. Had it rebalanced at Six States in Pasco, WA and it drove like new.

I've had a similiar situation that ate my lunch. It turned out to be rear brake rotors severly warped. In that case you had to let them get heated up then it felt just like a U-joint or tire. Rear rotors have to be warped pretty bad to start making themselves known so when they do you don't usually suspect them.

On another HD it was the aftermarket (dealer installed) chrome rims that were not hub centric to the truck. It needed special lug nuts to center it on the HD and the chrome ones they put on didn't do it. That took the better part of my week (just like you're doing) to pin down. I even swapped my wheels on to try and figure it out and must have rebalanced the wheels four times, as he bought new tires in the middle of the mess just like you and they didn't balance on my machine so I redid them.

It's a PITA, good luck.

Vernon

Humm thanks for the advice guys..

I live Ontario, so what would Six States be? just a good frame/axle shop?

Check your carrier bearing if it has one. A bad ujoint can ruin them also.

Here is a link , this fellow claims his sway bars stop frame beaming and spring rap ,http://fredericoperformance.com/

We had a truck with the same problem a while back at pretty much those speeds , turned out to be some bad berings in the axle, the truck was not old either...