I have just changed rear tyres - Michelin PS2 brand new - full thread. Fronts are half gone thread wise.

I can now definitely hear the front diff making whining noise when I go off throttle mainly 1st, 2nd and third.

Porsche Tech told me this is normal unless I change all four tyres.

WTF?

My front diff is definitely noisier (rattling wise) when I am on Michelins comparing to Pirellis but I never hand such pronounced whining. Diff is definitely working overtime...

Any of you guys having this?

Tanx.

 

May not be your diff. It could be your power steering reservoir. Does the noise continue when the clutch is engaged?

 

is it a high pitched sound?

 

No. Sounds like a bearing sound. Will record from benath the car today.

 

Here we go; 1st gear up to 4K rpm then clutch in/out and off throttle. It seems it is coming from the front diff. Is it possible that tyre circular difference front/rear would put front diff under such strain to make such noise?

http://www.communicormedia.com/Porsc...-frontdiff.mp3

 

What are the tire sizes?

 

Does your PSM activate at all when you're driving?

 

Stock. 295/30/18 and 225/40/18.

 

No it does not. Works normally.

 

I am down to front diff or bearings in gearbox. My Porsche tech tells me two gearbox bearings can be swapped without dropping engine and gearbox? Aperently some lids open on gearbox and you change frommthere? Which bearings are those?

 

Thanks to sql_pl...

Same problem here. So if you hear any whining (not originating from your wife or girlfriend) but from the gearbox, don't delay! Also inspect those mounts!