Vibration

[That986]

Holy crap, this guy will take his entire car apart at this rate.

To the OP, do the small stuff first like control arms and alignment before stripping the entire thing.

[tlc356]

Have you got a friend with a Boxster/Cayman? If yes, swap the other car's mounted wheels for a quick check. If the problem goes away. get new tires for your car. If not, don't worry about tires and go after the other isues.

[BYprodriver]

Originally Posted by That986

Holy crap, this guy will take his entire car apart at this rate.


Good point, when building anything start with a strong foundation. The rear wheels are highly suspect! Have them put on a wheel balancer without tires or weights to see what you are working with.



To the OP, do the small stuff first like control arms and alignment before stripping the entire thing.

Alignment won't cause vibrations

[nicecar]

wheel out of round is easily achieved by hitting curb once. Vibration gets worse with speed in my case.

[AZ986S]

Good point, when building anything start with a strong foundation. The rear wheels are highly suspect! Have them put on a wheel balancer without tires or weights to see what you are working with.

Alignment won't cause vibrations.

I just had all 4 wheels inspected and the 2 rear straightened (.035 and .060).
Then all 4 wheels/tires were Hunter roadforce balanced.
How would a reputable shop (Wheel Specialists, Tempe, AZ) verify that the straightening was effective? I would think without the tire mounted, but I didn't ask or witness it.

Unless extreme, I would tend to agree that alignment would not cause vibrations.

[nicecar]

Well there is the problem.....if it is vibrating then it's not straight.It is probably much better butt....Did I miss the post where you mentioned having the 2 rears straightened? High speeds low profile tires on a preformance based platform you wheel feel it so much more even if only off a little. sometimes budget restraints steer people to straighten. Got someone to loan a set for diagnostic purposes as mentioned in a previos post? I would gladly loan mine but my left rear is off a little as well.

[nicecar]

I see where you mentioned the bent rims in the original post so I did miss it. IKO look no further than the wheels. Human eye cannot see the deviation.

[BYprodriver]

Originally Posted by AZ986S

I just had all 4 wheels inspected and the 2 rear straightened (.035 and .060).
Then all 4 wheels/tires were Hunter roadforce balanced.
How would a reputable shop (Wheel Specialists, Tempe, AZ) verify that the straightening was effective? I would think without the tire mounted, but I didn't ask or witness it.

Unless extreme, I would tend to agree that alignment would not cause vibrations.

New wheels typically need 1/4oz weight to balance them, I would guess despite Wheel Specialists best efforts your rear wheels require a full 1oz just for the bare wheel.
Before debuting a unknown wheel on your car, always have it spun on a balancer & observe the up & down "hop", as well as the side to side movement to see what you are dealing with. Especially with new wheels since often they are non-returnable if a tire has been mounted.

[AZ986S]

Well today I went back to the tire and wheel shop to have the wheels checked again for out of balance. I've been battling the same vibration issue at 70 mph and higher.

The shop says all 4 wheels roadforced balanced less than 10 lbs and all is good as far as the wheels are concerned. So that leads me to believe that the suspension or steering is the culprit. Since I've observed no slop in the steering at all, and it is very crisp, I believe the LCA bushings or balljoints must be worn.

I have not replaced any suspension components other than the rear shocks after I bought the car last year. Front shocks rebound fine, no leaks. LCAs look old. Any way to tell for sure? If I do LCAs, should I also do the track arms?

[That986]

Originally Posted by AZ986S

Well today I went back to the tire and wheel shop to have the wheels checked again for out of balance. I've been battling the same vibration issue at 70 mph and higher.

The shop says all 4 wheels roadforced balanced less than 10 lbs and all is good as far as the wheels are concerned. So that leads me to believe that the suspension or steering is the culprit. Since I've observed no slop in the steering at all, and it is very crisp, I believe the LCA bushings or balljoints must be worn.

I have not replaced any suspension components other than the rear shocks after I bought the car last year. Front shocks rebound fine, no leaks. LCAs look old. Any way to tell for sure? If I do LCAs, should I also do the track arms?

You'll probably find that the tuning fork bushes are worn and tbh there's no real way to just visually check them. When i replaced mine the old ones "looked fine" but you could virtually bend them in half with very little effort at all.