Steering wheel judder / vibration when driving fast

[type-r]

When driving at 100mph + (off-road, of course) in a 997.1 C2S, I am experiencing the steering wheel giving off a rather noticeable vibration. Could the wheels need re-balancing or at that speed, would it indicate something different maybe track rod ends, or maybe the diff possibly?

At speeds below 100mph, no judder or vibration at all.

[Hilux2400]

Most likely wheels need balancing. Weight might have dropped off, or you have picked up a large screw in the tyre which is causing the imbalance and hence the vibration.

H

[Hilux2400]

Most likely wheels need balancing. Weight might have dropped off, or you have picked up a large screw in the tyre which is causing the imbalance and hence the vibration.

H

[Rockster]

type-r said:

When driving at 100mph + (off-road, of course) in a 997.1 C2S, I am experiencing the steering wheel giving off a rather noticeable vibration. Could the wheels need re-balancing or at that speed, would it indicate something different maybe track rod ends, or maybe the diff possibly?

At speeds below 100mph, no judder or vibration at all.

As others have offered balance is suspect. Alignment comes next.

There's something to keep in mind about tire balance. Assuming as is the case most of the time the balance starts out ok it can go off as the tires wear. The heavier areas wear away and then the tire is no longer in balance.

A few times it has gotten so bad I've had to have the tires rebalanced. The vibration comes on at higher speeds. In my experience below 100mph but over the speed limit.

The service manager and techs I've talked to tell me this is more common with the Cayenne and its huge tires but can happen to even the lowly Boxster, which is the car I've had to have the tires (17" no less) rebalanced.

Oh, this was done at no charge to me.

[nxi20]

The other suspect is that the tyre(s) have rotated on the rims, so even though nothing looks amiss (weights still in place, no strange wear etc.), the weights are now in the "wrong" place wrt to the tyre. My GT3 has often rotated it's rear tyres well over 90 degrees before they're worn out. Even the fronts move a bit due to braking forces.

[Fish]

Also check you steering damper is ok

[kbooker]

I had this problem a few years ago on a 993, the root cause was damage to the inside of the rear o/s tyre wall, a small "egg" or "lump" had developed, worth checking the condition of all the tyres before you spend anything...

[type-r]

Thanks for the replies. Will start by checking wheels and tyres and work from there.