So I took my car in to have the service shop look into an anoing clack/clunk noise that only occurs after some 20 minutes of driving.

Turns out that the front diff needs to be replaced.

Front differential assembly part number: 997 349 020 50

The car has around 104,000 km on it. Has anyone had this issue, or had to replace the front diff?

As I understand, this is something incredibly rare - the mechanic I'm working with hasn't seen this issue ever.

The factory part is $8500 (Canadian)! Online there are a few for $5600 (US).

Would really welcome any info on where to source a cheaper one, re-machined or other than OEM ... Please send all ideas this way.

Just damn bad luck. This occurred just as I was about to replace the VTGs and ICs with a nice tune

Now everything has been put on hold

 

Just a thought, why don't do RWD?

 

I live in Vancouver, so it's wet quite often.
...But at that cost, it may make sense to throw the money into a GT2 aero, slap some badges on it, keep it rear wheel drive and call it a gt2 LOL!
...that's my attempt at humour after being handed the news

Just sucks!

 

My front diff went at 37,000 miles....I am going down the GT2 road. Like you the project is currently on hold. I hope to starting moving forward with the next few weeks.

See my project/info at:

https://www.6speedonline.com/forums/...ully-done.html

 

Hey Vid, read through your thread. There was a post where you found used diffs with a 90 day guarantee - can you tell me where this was?

 

LA Dismantler. I believe they were asking $2500 USD a piece but they could not confirm mileage on either unit.

http://www.ladismantler.com/

 

I haven't had this unfortunate failure on my 997 TT. I did have a front differential failure on my 996 C4S. The Porsche dealership told me that it was not a servicable part and it needed to be replaced. The part alone was ~$7,000. I ended up having my independent mechanic fully rebuild the differential with entirely new parts. It took him about 2-weeks to get all the parts in from Germany and around the U.S., but he got it done for about $3,200.

You might consider speaking with some Porsche mechanics in your area to determine if this route is possible for you.

 

Hmm, interesting idea. Probably won't work for me. My service shop is solidly busy so I don't think they would want to take a project like this on. I'd have to dedicate some time to find the right indy shop to help support and my time is a little short too

Best bet is to try to locate a used part.

 

That sucks my friend!


There MUST be another solution as in rebuilding it solution! There must be a shop that can rebuild this to "like" new for the cost of a used diff, but at least you know what you are getting with a rebuild diff.


Thanks


Bobby Ali


ba

 

Are your tires Stock (side) ? I have heard that running wider tires or a staggered tire set up can cause this issue?


Just looking to confirm.

 

Yea I would like to know what it is that causes that failure, oil leak?? Tires?? Manufacturing flaw??

 

i have seen used 997 diffs for 1-1.5k on ebay.

are you running factory size tires?

 

Running front tires and rear tires that are not within spec will cause the front dif to die. There use to be a tool here to put in the tire sizes to see what the ratio was and whether it was within spec.

 

Proper/standard tire sizes, that wouldn't be the issue, nothing exotic.

245x30x20 and 325x25x20

No leaks, it's just a metal on metal clang noise thats not loud and appears at speeds of under 25kph and mostly on a bumpy or uneven surface.

 

Any chance the diagnosis is wrong? When I had my GMG springs and sways put on there was a little clunky noise over rough roads and the shop said it was the link between the front sway bar and whatever it connects to. Haven't heard any noises in a while after the suspension got broken in.