996 C4 Front Differential

My 2004 996 C4 Cab has just come back from its annual service with the news that the 'query' front wheel bearing noise, has turned out to be the front differential - bearings ? Advice has been to acquire a second hand unit (ebay ?), and swap out, but I am also pursuing possible 'repair'. I am 'drained' by the idea that this 'supercar' engineering, has worn out bearings in a Getrag unit at 56,000 miles. I certainly did not realise this was a potential problem (another one) ! Has anyone had experience of this, and willing to offer feedback and possible people to contact. With a new unit currently on 'special offer' @ £4465, I need other options !!!

It might be worth trying Autofarm, I thought i had a similar problem last last year but luckily it turned out to be a wheel bearing, but I'm pretty sure I remember one of the service guys telling me he had to have the bearings replaced on his front diff and if mine were faulty they could outsource it to the same firm. Best of luck Andy

A quick Google threw up these threads: https://rennlist.com/forums/996-forum/782187-996-4s-front-diff-rebuild.html https://www.6speedonline....ront-differential.html Seems like it isn't that difficult to replace the bearings. If these guys are DIYing it, I would have thought an it would be a doddle for an indy.

If you find a local transmission specialist, they are likely to repair at fraction of the cost. Bearings are relatively straight forward providing they are the correct type and stressed for load and temperature correctly.

All Apologies for the delay, personal issues in the current climate, mean't the cars fell to the bottom of the list ! I'm still investigating a couple of options. My Indy doesn't want to work on the diff as Porsche do not supply bearings, and the task or sourcing doesn't make it worthwhile. I've contacted a transmission specialist, and they don't want the problem of removing/refitting diff. I did not expect it to be so difficult ! More work required. Will update as and when. thx

Try https://www.mackie-transmission.com/ Would the Indy remove and refit ?

Thx for comment. Not sure they are keen as it takes up their ramp while the diff is being repaired. They were happy to consider a swap over as it's a quicker operation. Maybe I can look at removal some other way, I'm not up to it myself ! I've seen the website, so useful reference - thanks. regards

Hi, did you manage to get this resolved?

Hi There, Yes, I should have posted something ! After contacting various people, I took the car to Sports and Classic, who gave it a good going over. Initially, they suspected a wheel bearing, but were also concerned with the road noise of the five year old front Pirellis. They changed the tyres and a bearing, and also ran the car with dummy front shafts to remove front drive. Although the noise level was reduced, they thought there was still something audible. Referral to some of their contacts with Porsche experience, concluded that the noise was the 'norm' with the C4 ! This was a surprise to me, but I collected the car with the knowledge that it had been fully investigated ! With last year, the car only did about 600 miles, but certainly to me the noise is now barely noticeable, so the tyres appeared to have be exaggerating the noise. The wonders of Porsche Engineering !!

I thought my rear hub bearings had worn as the noise from the rear was very bad, fortunately I have a very good Indy here in WA plus one of our members owns tyre, suspension and geometry place so could offer an explanation, only 3 years old with over 3mm tread! Unfortunately could only get the same again here, wanted Michelins, so will have the same again I suppose[ ], Its not always what you think[8|] hopefully can get Michelins next time.