Vibration at 100+

Hi all, (996 c4s 2003) Over 100 I seem to have quite a noticeable vibration in the car and steering wheel. I have replaced alot of suspension parts recently so could it just be the tyres? Backs need changing and the fronts are over 70% worn. They are p zeros, looking to change to Bridgestone, any recommendations? cheers

I would say its likely to be tyres or wheel balance related. Obviously worn tyres are not to be recommended. I have Bridgestone Potenzas on my C2, and grip is good in the dry, but in the wet I consider the grip pretty poor. Certainly nowhere near as good as the Michelin Ps2s fitted to my last 996. Also the Bridgestones are noisy, creating a lot of tyre noise. Hope you sort out the problem.

On which track day experience did you notice this problem? Or on what stretch of Autobahn?

I know some love them but I hated the P-Zeros on my 986. I suffered vibration and shocking tramlining even when they were fairly new, both isdues cured at a stroke when I fitted Conti Sport Contacts.

I had this problem and I had the wheels balanced and it is 95% cured. I say so as some stretches of road, depending on surface and camber, still give the slightest vibration but hardly noticeable now. I would strongly suggest researching for a good reputable dedicated tyre centre to balance them though. I had mine done initially by a porsche specialist during a service and when I took it to a dedicated tyre centre, as the vibration wasn't cured, the balancing was way off. Hope this helps. John.

Rhys, Whilst vibration due to wheel unbalance can occur at very high speeds, it generally manifests itself before or around the legal limit. Although I suspect that it's due to your well-worn tyres - which certainly you should replace before looking elsewhere - it could be due to wear in one or a number of your driveshafts. Worth a look if replacing the tyres doesn't help. Jeff

If your feeling the shaking in the steering wheel while doing 100mph. put the car in neutral and let it coast. Don't touch anything (the brakes, clutch nothing) . If it still shakes, its probably something in the front end: tires, wheels out balance, wheel hubs etc. If its shaking and you put the clutch in and it stops, may be in the drive-line, trans etc. If your feeling the shaking in the seat of your pants, check your rear tires, could be drive shaft / u joints, rear wheel hubs etc. Is the wheel shaking up and down or side to side? If your feeling the vibration when on the brakes, check your front rotors, wheel hubs. Drive carefully and safely at all times

New to the club and the forum and this post has been useful. 5 days on on my 992 ownership and noticed a similar problem. Will get the wheels/tyres looked at as a first port of call. I’ve had the car looked over mechanically and no issue so fingers crossed it’s a balancing issue!

Broadly, if you feel the vibration through the steering wheel its likely the front wheels, if you feel it through the seat its the rear wheels...

Sorry to resurrect this topic, but during a couple of thousand miles road trip in Europe, I noticed NVH on different roads at higher speeds (95+) in my 2007 C4S tip cab, 74K miles, new Michelin PS2s all round, all suspension arms renewed 4K miles ago and no rattles. 4 wheel alignment by Meteor Motorsport after. No shaking through the steering wheel at all. What is the collective view? It is 'perfect' at British road speeds.