Vibrations at 65+ mph - 2003 Tahoe

[CEN2MENTAL95]

Hmmm....have you checked the ball joints?

 

[91RS]

A few other comments -

- tires were road force balanced. Didn't get the name of the balancer, but had a nice display that pointed out how much weight to add to the specific location.
- tires are goodyear wrangler - 245/75r16.

Roadforce balance checks the tire with a roller and gives a reading in pounds. 30lbs is the limit for P tires. It can only be changed by indexing (or clocking) the tire on the wheel.

 

[chh777]

U-joints, have had several of these and normally there is a front drive shaft joint out, none of them ever felt loose but they get just dry enough to set up a vibration. if you look close, you can see a little bit of rust dust seeping out of a cap seal.

+1

I had the EXACT same problem (vibration started ~60mph, got a little better above 70mph) and it was driving me nuts (ARRR )! I replaced the (rear) U-joints and the vibration is gone. The old U-joints were not loose at all and moved freely.

I'll be replacing the fronts when I have it on the rack for diff/t-case fluid change.

 

[Gzes]

My guess is tires. My hoe shook like hell on road over 60 then put the new shoes in the front and havnt vibrated at all

 

[CEN2MENTAL95]

It's possible the tires are out of round or a belt is internally lose. It happens.

 

[DMSchuler]

Guess I didn't know what roadforce balancing meant. There were no rollers involved - just mounting the wheel assembly on a spindle and then spinning the wheel.

Interesting (maybe) observation from the guy at the tire shop: I asked why the PO wouldn't have balanced the tires, his response was "Probably had the tires sitting around and threw them on the truck just to sell it". I guess the tires are still suspect. Everything seems tight now that the tie rods are replaced.

How do I find a shop that can do the roadforce balance, and is there anything specifically I should be asking?

Thanks!

 

[91RS]

A dealership will be your best bet with the roadforce balancer, GM dealers are required to have at least one for warranty work. Just tell them you've already had them balanced and it still vibrates and request that they be checked for roadforce. Just checking the roadforce won't cost any more than a tire balance (usually $40) but if any are out of spec and need to be indexed, it will cost you per tire (usually however much and mount and balance costs). If the roadforce measurement can't be brought into spec with indexing then the tire is no good.

Do you know how old the tires are (by the date in the DOT number)?

 

[DMSchuler]

Don't know how old the tires are. Where is the DOT number, and how do I determine the date from there?

 

[91RS]

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=11&

Some tires only have the date code on one side, so you might have to look on the inside of the tire depending on which way the tires were mounted to the wheel.

 

[DMSchuler]

15th week of 2000. Tires are older than the truck, so seems to support the suggestion that the guy just had them sitting around.

Damn. Not looking forward to buying new tires!