Just had 5mm OEM spacers front and rear installed on my 991 and have now found that the car tracks considerably more at highway speeds. Has anyone else experienced the same?

 

Nope. That should not have been enough for you to feel the difference. Did you get 4?

 

5mm all around front and rear.

 

Taking back to the dealership for evaluation.

 

I ordered mine with 5mm from the factory and have no issues. Perhaps they align it differently?

 

That is what my porsche contact is saying. He thinks its likely the alignment. Guess will try that first and see how it goes. Thanks for everyone's input. Love the way they look on the car but not thrilled the way the car is tracking on the highway. Hopefully it will be resolved soon.

 

I doubt that the alignment spec is different with spacers. He might be out of alignment though.

 

This reassure my desicion that despite the higher price, I always order them factory installed, never had a problem.

 

could be some grit stuck between the hub and the spacer, or spacer and wheel. An uneven surface contact would cause the wheel to wobble ever so slightly. The wobble might not be noticeable as wobble, but it could affect the way the tire tramlines / picks up on road grooves.