Did you speak with the dealer???

 

I'd have driven the car to the nearest Porsche dealer, asked for (and paid for) a definitive diagnosis and cost to repair- let THEM come up with "improper tire sizes on car", then gone back to the selling and inspecting dealers. Without tipping your hand with the new dealer about the whole prior history- since that would likely cause them to cover up (just because they don't want to get embroiled in a legal battle.)

Anyway, too late for that, but in case others find themselves in such a situation...

 

plus 1 on this...

 

I did take the car to Porsche of Albuquerque without going into the details of my predicament. Just that I was passing through and needed a diagnosis. They identified the front diff, but did not go into possible causes of it going bad.

And yes, I too agree that I cannot rely on just a PPI, Carfax and photos to assess a clean bill of health. There doesn't seem to be any accountability anywhere. Clearly will not do that again.

 

I just got off the phone with the Service Manager at Park Place Porsche in Dallas - the folks who did my PPI. They are denying that they did anything wrong - even suggesting that the tires must have been switched out between when the PPI was done and when the car was picked up by me.

There really is no accountability in this world...

 

So I've got the front end disassembled. The main issue is not the diff - it's the left wheel bearing. You can see a video of it here:

https://skydrive.live.com/redir.aspx...!iyaBVxDoac%24

It's the second file there.

I've also got a 2nd used (supposedly good) diff in hand and have also torn down my diff a little bit and here's my current diagnosis:
- The actual diff and bearings seem ok. No strange noises.
- The left output seal was leaking.
- No idea if the viscous coupler is good. Seems to want to rotate at the same speed as the diff. If you spin both the outputs fast, you hear a splashy, liquid-y sound from the coupler. Might be normal.
- The tailshaft isn't quite so nice. It is slightly louder than the second diff. But not very severe - me and my local shop both were second guessing ourselves if there was actually any difference. Just a tad bit of a crackly sound. Like a light grinding/gritty sound once in a while. Definitely not the root cause of the overall issue I've been facing. That was definitely the wheel bearing.

Anyways, I'm going to try and see if I can take apart the tailshaft and redo the bearings. I'll keep you guys posted.

 

I bought my car this way (remote PPI, carfax) and came out ok. I suppose that the dealer who did the PPI and claimed that the tires had been swapped is also going to claim that the wheel bearing was swapped out also??

If I were you, I'd be asking the dealer who did the PPI for a refund. It won't cover your costs, but it would help. My dealer PP cost me $500.

GL,

Jon

 

I did manage to get a refund from the dealer that did the PPI for the cost of the inspection ($199 @ Park Place Dallas). But it was not easy. The service manager was so insulting over the phone and adamant that they did nothing wrong that I then called Amex to file a dispute on the charge. I also wrote a couple of reviews online detailing my experience. The next day, a customer advocate responded to the review on dealerrater.com and asked me to call him. This person was a lot more reasonable to deal with. He also kept telling me that his service team was adamant they did nothing wrong, but Park Place didn't want bad press so they would do a refund. I took it.

Moral of the story: ALWAYS do a test drive. Nothing you can do will reduce the risk to 0, but do the most you can.

 

Well. After wrenching for 3-4 days, I've done both wheels bearings, redone the boots on one axle, redone the diff seals and rebuilt the tailshaft portion of the front diff.

Noise. Gone.

And judging by the front wheels breaking loose tonight in the cold/wet when getting into boost, I'm guessing the coupler is fine.

I will post a DIY on the tailshaft rebuild at some point. Wasn't too hard.