Steering shake after alignment

[Bala]

After the full suspension overhaul, bearing change, tie rod change etc I took the car in for a full alignment and road force balancing to a local Porsche shop. After the alignment and balancing the front wheel vibrates and I can feel it in the steering. The front also feels like its kind of uncontrollable at high speeds (75+). Almost like its got no grip.

The steering never vibrated even after the suspension overhaul work except it was cocked to the right side which I attribute to not putting back the tie rod to original mark. They said they did it to factory specs and asked me to bring it back in.

Question is: what specs should I have it aligned to? Normal street driving is what I do.

[Johnny Danger]

Did this service involve getting new tires ?

[san rensho]

Did you drive the car at speed after the suspension rebuild and no shakes? If not, then I would say something is loose in the new suspension.

[Bala]

Originally Posted by Johnny Danger

Did this service involve getting new tires ?

No. Same old tires.

[Bala]

Originally Posted by san rensho

Did you drive the car at speed after the suspension rebuild and no shakes? If not, then I would say something is loose in the new suspension.

Yes. I did drive the car at hogh speeds after the rebuild. I had torqued them all to spec as well. You may have a point on something coming loose but, this shop is well known Porsche so I assume they did the right things. I was even watching from far and can't complain about how they went about the whole process.

[Bruce Wayne]

1. check the wheel weights - have you lost a weight and they are out of balance

2. check the tyre wear across the face is it even ? if you have worn shoulders after alignment it could cause vibration.

3. are the tyres worn consistently and evenly round

4. is there any tread demlaination on the tyres or flat spots

[wvboxst3r]

My guess is flat spots on tires. Had mine up yesterday and noticed the inside of the front tires was cupped or flat in spots. When I mentioned this to shop I was told that was from the toe out and not pushing the car on all corners. So I may have some of the toe adjusted and buy new fronts because the car would shake bad with these tires.

[Bala]

Thanks Bruce and WV. Good points. Will check it out. It may be time for new tires after all.