C4s road noise

Chuckmiester · 29 Apr 2013

I have a 2003 c4s which seems really noisy on the road. It sounds like tyre noise but having not been in another one to compare it to I'm a little concerned it could be a wheel bearing or may be the front diff. The sound doesn't alter when I go around a corner and I am on continental sport tyres. Thanks in advance for any replies.

gothicsanta · 29 Apr 2013

Shouldn't be noisy, mine isn't...

isysman · 29 Apr 2013

I suppose it depends what you're used to? My C2S was quite noisy I thought compared to non soft tops but then I got my turbo and I wish it was as quiet as my C2S.

GT4 · 29 Apr 2013

What is the tyre brand and tyre model?

Diffrent tread and compounds make an enormouns difference in road noise.

911seeker · 29 Apr 2013

I changed from Bridgestones to PS2s recently and the reduction in tyre noise was vast.

isysman · 29 Apr 2013

My Turbo has Bridgestones, I'm thinking that's the reason.

Maxie · 29 Apr 2013

Chuckmiester said:
I have a 2003 c4s which seems really noisy on the road. It sounds like tyre noise but having not been in another one to compare it to I'm a little concerned it could be a wheel bearing or may be the front diff.

Tyre roar is common across the 996 and 997 range owing to a relative lack of sound deadening (to keep cars as light as possible). There is even less sound absorption materials on the GT3 cars. The problem appears to have been licked on the 991 series. I notice a lot of tyre roar in my 997 (I run Bridgestones - if it makes a difference). I have been advised that a decent sound-proof kit will normally kill the road-noise. Whilst this might seem like a good idea, it will be a specialist job as the seats and the headlining will all have to come out before the existing sound-deadening material is replaced with one of a better quality.

~ Maxie

infrasilver · 29 Apr 2013

How old are the tyres, this can make all the difference. If they are old, which is possible on a that doesn't do much mileage per year, like a Porsche, it may create noise through the car.

Chris W · 29 Apr 2013

infrasilver said:
How old are the tyres, this can make all the difference. If they are old, which is possible on a that doesn't do much mileage per year, like a Porsche, it may create noise through the car.

I suspect it could be this. Fronts wear very slowly and age gets the better of them rather than wearing out.

Was going to ask if they were Bridgestone as they are generally noisier particularly through the winter months, but Conti are not known for this.

Does the problem get much worse on concrete roads over tarmac? E.g. the southern bit of M25 is awful in most cars.

ragpicker · 29 Apr 2013

I am having exactly the same problem on my 2003 C4S!

It has Pirelli's on at the moment (until Thursday when it will be PS3's).

There is a constant low level hollow whine which gets worse with increasing speed. The pitch also gets higher with the increased speed.

The gear makes no difference to the noise, nor does depressing the clutch whilst the noise is being made.

It seems not to begin as soon as you get in the car, more after things have warmed up a bit.

My mate who is a Porsche Indy in Teesside has driven it and (although I think it is a wheel bearing or the front diff) he thinks it is the tyres. He says certain tyres are renowned for it.

Well, time will tell on Thursday!

I have driven it for hundreds of miles like this and the noise only ever reaches a certain severity and never seems to cause any damage or associated other sounds.

scottuk · 29 Apr 2013

My '03 C4S was quite noisy on poor road surfaces, also had worn Pirellis, changed to Bridgestones at the beginning of the year, and have had a noticeable difference in the drive of my car and cabin noise reduction. But I would say far from Lexus quite, :grin:

Chuckmiester · 30 Apr 2013

GT4 said:
What is the tyre brand and tyre model?

Diffrent tread and compounds make an enormouns difference in road noise.

it is on continental sport contact 2s all around, I can't tell you how long they have been on the car as they were on when I bought it.

Chuckmiester · 30 Apr 2013

Chris W said:
infrasilver said:

How old are the tyres, this can make all the difference. If they are old, which is possible on a that doesn't do much mileage per year, like a Porsche, it may create noise through the car.

Click to expand...

I suspect it could be this. Fronts wear very slowly and age gets the better of them rather than wearing out.

Was going to ask if they were Bridgestone as they are generally noisier particularly through the winter months, but Conti are not known for this.

Does the problem get much worse on concrete roads over tarmac? E.g. the southern bit of M25 is awful in most cars.

It doesn't seem to get any worse on different surfaces, it sounds like the same problem that ragpicker is having. Well have to see what difference new tyres make to his on Thursday. :thumbs:

lofi · 30 Apr 2013

Chuckmiester said:
GT4 said:

What is the tyre brand and tyre model?

Diffrent tread and compounds make an enormouns difference in road noise.

Click to expand...

it is on continental sport contact 2s all around, I can't tell you how long they have been on the car as they were on when I bought it.

Yes you can. There is a code on the tyre wall that will tell you what year they were manufactured. Can't recall what it is but a web search will find it.

sking · 30 Apr 2013

My 996 TT is also very noisy on coarse tarmac. I am running on newish Continental Sport N2s and it is definately tyre noise as it varies dramatically with road surface. On smooth tarmac it is fine. Last car was a Boxster s with Pzeros on wide rims and it seems much noisier than that. Still a bloody nice car though.