Has anyone experienced shimming or vibration of the steering wheel when going past 50mph? I also notice that steering feels a little loose at high speed as compare to my past sports cars.

My guess is bad balance or perhaps flat spot on the tire. The car (2008) has only 4k miles so I am not sure why it would lose balance. I checked tire pressure also and it's within range. In fact, I dropped it to "comfort" settings just to see how it may change the feel.

I am taking the car into service this week but I wanted to do some homework on what may be causing this issue.

Thanks in advance!

 

could be the balancing or a slightly bent wheel.

 

Thanks Neil - I am hoping for just balancing issue. Wheels look immaculate but I guess you never know.

 

Agreed, I'd say balance the wheels and go from there... Are you feeling it through the steering wheel I assume?

 

Just another thought, does it happen during light braking and then go away on firm brake application? Several people have noted this and some had installed wheel spacers and some hadn't. Could be slightly warped rotors( which some say occurs more than Porsche wants to admit) or pad issues. mine was rotors and replaced via warranty. Just my $.02 Cheers

 

for balancing, try to find a shop that has a road-force balancer.

 

+1, warped rotors was my next thought. I'd start with making sure you didn't throw a weight though.

 

thank you all for the great advice.

Vibration is felt only on the steering wheel and it's nothing excessive - just very annoying to feel slight shake when going past 50mph. I have to admit that certain roads are worse than others.

I don't feel any more vibration with the brake on or off so I think the rotors are OK.

 

Does the vibration feel like you are driving over a very long fine ripple strip and is it there when you back off on over run?

 

speed21 - yes, sort of feels like I am going over undulated pavement - steering moves side to side and it does dissipate over smoother surface. I can totally see a dealer saying it's normal ...

 

Well, I spoke with the previous owner and he said it was due to flat spot on the tire (due to car not being driven too often). Can this be addressed through wheel balance? I guess it can't hurt...

 

I'd definately clear up the wheel balance possibility first before anything else. The flat spot issue can be checked at the same time.
Now If that doesnt fix it then you may well have a front diff problem like what i had. My steering wheel never wobbled side to side as such.....I just felt this high frequency vibrating through the steering wheel and pedals accelerating over 80kph, the vibration also developing into a pulsating the faster you went and, also inder braking. You could feel it through the pedals too.The car didnt feel very stable either the faster you went over 90kph, especially when nailing the throttle.