Dodged a BULLET!

[wwest]

Blessed be the INTERNET!

I had convinced myself, absolutely, that the front differential itself or bearings had failed in my 2001 C4. Nutating bearing noise at 65-68MPH and around corners and the whole bit.

Luckily I had previous experience with tires going noisy after a few thousand miles. Searched the internet for Bridgestone Potenza RE730 and discovered numerous complaints of noise developing after 5k miles or so. Two or three even said they thought the noise was due to bearing failure at first.

I have run Bridgestone Turanzas on my Lexus vehicles since ~1993, so I had absolute faith that the tires were't the problem.

So, do I take the car to Porsche and have them "judge" the problem, knowing full well that their answer will be a function of $$ signs, or do I replace the tires on the chance they are the problem?

Installed Michelin PS2s, Costco, today and the car runs as quietly as the day I picked it up at the factory.

[PorschePRH]

When this happens, do what I did and find a friend that will lend you his tire/wheels for 30 minutes to find out. In my case, it was the tires and I thought it sounded very much like a bearing. But really, if the noise changes at all over the different road surfaces, it's not a bearing...

Edited July 14, 2005 by PorschePRH

[Orient Express]

I had installed Bridgestone Potenza RE730 on my S4 2 years ago, they were nice and quiet for about 1500 miles, and then started the noise that sounded like a bearing grinding. It got so loud that I sent them back to Tire Rack, and got Michelin Pilot Sports and have been happy ever since.

I have never had good luck with Bridgestone tires. I have had tread separations, uneven wear, and the noisy treads with them. I have been sticking to Michelin on all of my cars, and have not had problems.

[PeterC4]

I have Pirelli PZeros, they're noisy at about 90 kms.

[cab713]

Hi All,

I just replaced my stock turbo twist 18 and tires that were totally shot with some SSR GT3 18" wheels with PS2's. I did notice a drastic reduction in road noise upon switching, but on one particular section of highway (60 miles of it) I now notice a droning hum at speed 70-90 mph.

I can't say it wasn't there with the old tires since they were so loud, but this section of highway is almost miserable.

Is there something I can do to eliminate this? Any ideas about what to check?

[djantlive]

Some times rotating the tires help. If they are directional and F&R sizing is different, there isn't much you can do.

[SFBayArea Jimmy]

Hi All,

I just replaced my stock turbo twist 18 and tires that were totally shot with some SSR GT3 18" wheels with PS2's. I did notice a drastic reduction in road noise upon switching, but on one particular section of highway (60 miles of it) I now notice a droning hum at speed 70-90 mph.

I can't say it wasn't there with the old tires since they were so loud, but this section of highway is almost miserable.

Is there something I can do to eliminate this? Any ideas about what to check?

may be you can play around with tire pressure a bit to see if that helps. I am happy with 36/40 ( Porsche recommmended 36/44 for C4S ) :thumbup:

[cab713]

Thanks for the recommendation. I've got 35/42 in them now, but I'll drop the pressure a bit more. I was looking for information on rennlist as well, and it seems the general though is that fast car + big tires = road noise on certain types of roads.

Any thoughts?