bigger problem than I thought?????

[dave1123]

I just got my '96 at the end of April and I drove it home and noticed a vibration. I posted a thread right away and was told it was probably a tire balance issue, which I thought was it too. I took it to the local Porsche dealer in town here because they have one of the most state of the art road force tire alance machines in this area. I took the service manager for a ride in the car so he could feel the vibration and see what he thought. he ssaid the front tires didn't seem to be out of balance and he was feeling the vibration coming from the rear end. *** could that be? the vibration start between 65-70mph and then stays at higher speeds. I tried it in 3rd, 4th and 5th gear and still the same vibration. the car was tracked three times before I bought it and the guy I bought it from is a VCA memeber and says he never noticed the vibration. what could it be? Gerald Smith (VCA MN) drove my car and he thinks my U-joints might be worn. what else could cause this problem? the Porsche Dealership is going to do the road force test on wednesday of next week and I'm hoping it has to do with the rims and tires.

 

[99 R/T 10]

Flat spots on the rear tires?

 

[dave1123]

tires are brand new, but still might be the case

 

[Snake Bitten]

[quote Gerald Smith (VCA MN) drove my car and he thinks my U-joints might be worn. what else could cause this problem? the Porsche Dealership is going to do the road force test on wednesday of next week and I'm hoping it has to do with the rims and tires.

[/QUOTE]

Not U-Joints...I thought tie-rod ends, control arm bushings...

Has your 999/998 recall been done?

We can put it on a lift down at Greg's and check out several items...shouldn't be too hard to run down...

 

[dave1123]

I was just going to call you, and ask that very same thing. Maybe throw on greg's extra acr rim and see if it is my rims and tires

 

[Snake Bitten]

Greg has some extra 18's off Glen's car...Give me a call in about an hour or so...

 

[dave1123]

alright..sounds like a plan

 

[Gerald]

THere is a certian machine that tests not only for alignment, but rim and tire out of roundness too. Usually dealerships have this..

Gerald

 

[joe117]

If it's not the tires, here's an idea.
The driveshaft can be clamped to the yoke on the rear end two ways. If it get's clamped the wrong way that can sometimes cause balance problems. I don't know of any way to check if it's right or wrong.
Just something to try if you run out of other causes.
It's not just a free check though. The yoke straps should not be re used.

 

[Tomer]

Per previous post, if you are not sure the yoke strapes were replaced when the recall work was performed, then
replace em to be sure!! Parts are cheap.

Tomer

 

[dave1123]

the recalls had all been done prior to me buying the car. and the Road Force Test is the machine that type of machine the checks a ton of stuff. Thanks for all the input.

 

[Jeff Torrey]

Dave- I just put new Pilot Sport Tires on my car. The tire shop was able to balance the fronts on their machine. But the rears were to wide to fit. So they put this sand in the tires, supposed to balance the tire when moving. Anyway I do not think it is working. You mentioned the front tires seemed fine to the Porsche guy. Could be the rears, my car is now acting the same. Will have to take the car in and get the rears balanced, pain in my ...asp

 

[Greg W]

My rear rims are bent, both of them. The balance shop did their best, difficult to even find a place to balance those wide rear tires.

Freeway vibration is actually worse now with my new tires, the theory is that the old tires were worn with a pattern the somewhat compensated for the bent rims. Vibration isn't too bad, so I live with it. New 18" rims (with cheaper 18" tires) would have been my best choice. Live and learn.

Greg W