Yet another steering vibration question...

[greenerob]

I have the exact same issues. Noone can find the culprit.

[shlim8]

Originally Posted by greenerob

I have the exact same issues. Noone can find the culprit.

Yes, I know, I've been following your thread with much interest. I should be doing the rotors and M030 next friday, when I get back home (me and the car currently outstation in the neighbouring country). The M030s have arrived at home, but now I'm still waiting for the strut mounts - thought I'll change those too, since labour is not cheap and they are 9 year old mounts, even if it's low mileage. And the new ones are updated 997 (front) and 987 (rear) pieces.

I also intend to do a Hunter Road force balancing, can't find one here, but I managed to locate one back home.

Will keep you posted whether those changes help/solve the problem.

BTW, do you know how they diagnosed the tie rod problem ? Frankly, my suspension components seem solid but I guess the forces when travelling at high speeds should be greater than us shaking the wheel or components for free play.

[greenerob]

The tie rod was shot and they could easily it was bad.

You must get a Hunter Road Force balance. It is the only way to go.

I will be getting on check this week. My problem is that the speed limit around this shop is only 55 for about 15 miles. The car rides near perfect at 55.

[shlim8]

I finally found a hunter roadforce balancing machine at the city I'm currently in and it turns out to be just one or two miles from my office !!

However, the balancing guy tells me that because I'm not using N spec tyres, there will always be vibration.... he was most reluctant to do the balancing for me and he claims he has another boxster customer who did it and complained all the way to Michellin (he was on michellins). To cut the story short, they road force balanced 4 times but still vibration... finally on a dare by the Michellin reps, he changed to N specs and viola, no vibrations...

Is there any truth in this ?? Porsche can only use N specs or there will be vibrations ?

Anyone out there with non N specs tires and no vibrations from the steering ?

Anyway just did the road force balancing, seems to reduce the vibration even more at low speeds but really haven't fully tested it out yet.

[BYprodriver]

Originally Posted by shlim8

I finally found a hunter roadforce balancing machine at the city I'm currently in and it turns out to be just one or two miles from my office !!

However, the balancing guy tells me that because I'm not using N spec tyres, there will always be vibration.... he was most reluctant to do the balancing for me and he claims he has another boxster customer who did it and complained all the way to Michellin (he was on michellins). To cut the story short, they road force balanced 4 times but still vibration... finally on a dare by the Michellin reps, he changed to N specs and viola, no vibrations...

Is there any truth in this ?? Porsche can only use N specs or there will be vibrations ?

Anyone out there with non N specs tires and no vibrations from the steering ?

Anyway just did the road force balancing, seems to reduce the vibration even more at low speeds but really haven't fully tested it out yet.

N spec tires are not required to have a smooth ride. I normally by Michelin PS2's for all my cars but don't pay the extra for the N spec.

[shlim8]

Finally had the shocks and springs out yesterday to install the M030 kit.

Practically every component on the front end wasn't in good shape. The shaft of the shocks shakes badly, the control arm main bearing moves laterally at the joint and the control arm link ball joint was alittle loose.

And without taking out the shocks and springs, it was not possible to detect any slop in the front suspension.... I've even had a mechanic swear that my car was "perfectly" setup.

Anyway, had the M030 installed and had the failing links and control arm re-installed (have to order for parts first), wasn't expecting much since not everything is in order.

BUT, wow, what a difference there is.... suddenly the car tracks around corners like on rails (whereas before it felt like it wanted to fly into the nearest greenery).

As expected the vibration is also greatly reduced and steering feel greatly improved, but not sure about the high speed vibration yet - will test tomorrow.

[harryrcb]

did I read that you had different tires in the rear than in the front? If so you will find high speed cornering not so much fun because you will be getting different grip levels from the different tires, I did that once and it was horrible, be careful.