Maybe - but at this point - I'd only use genuine Porsche (or perhaps the Shell oil discussed earlier - which appears to be where Porsche gets their oil from.) The Ravenol bottle is killer for filling it though.. so it's worth saving the bottle (I did..)

And - there is about $10 difference between Ravenol and the Porsche fluid (Porsche dropped the price).. so why Ravenol?

 

Here are some pics of X-fer case apart.

 

Quickster - remind me - what was your problem with the TC? And what did you try to fix it? BTW - wonderful pics, I might resize them a bit for you - they're a tiny bit on the large size

What's interesting is:

So we know it's made in Germany now - and can guess it's ZF or Getrag.. (the two big transmission makers in Germany.) The transmission itself is supposed to be a ZF - so I'm gonna guess so is the transfer case.

CORRECTION: 04/10/18 - In looking at used 958 Cayenne transmissions on eBay it becomes obvious that the transmission is made by Aisin, in Japan.

 

Please take all of the editorial liberty you want with the pics. I have more but these should suffice. The reason I took the case apart was to weld the crack at the drain hole. Coming from my aviation background I was not going to be satisfied with JB weld or some similar repair method.

As noted in the pictures the PO had the case replaced at some time earlier with the -08 revised one. I suspect that the case was replaced because they ran over something. I don't know for sure as I bought my PiG from an independent dealer. Regardless, my case failed due to the driveshaft coming out of the rear differential and before I could safely pull over to get out of traffic (only a few hundred yards) my case was literally smoked. This accelerated wear to failure happens as the clutches were trying to engage based on stepper motor input. My nearly fresh oil was black after this event. This "event" combined with the bent X-fer case cross member and bracket as well as a compromised rubber isolater in the cross member lead to premature wear on the case due to poor alignment as well (my thoughts). I assume it was going to fail soon anyway based on the difference in drive-ability immediately noticed with all of the repairs accomplished. This is the only plausible explanation we came up with. So......frame repair, new cross member, new case, new hardware all is back to like new condition.

I've now put several hundred miles post repair and I cannot believe how much nicer the vehicle shifts, accelerates, and decelerates.

 

awesome! Thanks quickster

 

I will be rebuilding mine ... I'm just trying to track info on the programming part after rebuild ... I do have access to Piwis 2 so its not a problem, but I need to know procedure. ( Some procedures like pinging fix require special values that have to be inputted )

 

I spoke with my dealer's part lead about the various part numbers I had seen on my receipts related to my last two transfer cases. Here is what I learned:

 

 

Please do consider a DIY while you do it. If you take the photos whilst doing it, I'll be glad to help put the rest of it together. It would be a really great contribution to the community knowledge.

 

Im planning to record video ...

​​​​​​What is holding me back is the software update part ... Im trying to track info about that, this might be critical part, Piwis can read write memory, it can process update as well as writing custom values.

So without solid information I can't proceed

 

Perhaps contact the chap who sells the parts - it seems he's responsive. And maybe your local dealer's service department might be of help?

 

 

Wow, this is a long thread...amazing that Porsche is not addressing this issue more seriously. Wife's 2014 CS had transfer case replaced at 25k miles, now at 51k I drove it yesterday and symptoms are back again..

 

 

Yesterday I was at one of two P dealers local to me that I do business with. While checking out some new rides, my salesman introduced me to one of their more senior technicians that happened to be in the sales area at the time.

In chatting with him about a number of things, we got on the subject of the 958 transfer cases. He mentioned the latest revision of the case (which we've discussed in this thread) and the associated new hardware like the vent kit, etc.

According to him, the issue has always been a contamination of the fluid. The total amount of fluid the TC holds is very little actually (1 liter or so?), so any small amount of contamination can have significant impact, and that impact specifically degrades the friction modifiers in the fluid which is at the root of the problem. In some cases a fluid change corrects the issue (which we've seen evidence of), and then in other instances the damage caused by the fluid contamination is more severe and thus permanent, requiring a TC replacement. He mentioned that the vent kit helps reduce fluid contamination, but it is recommended now that the fluid in those transfer cases (even the new design) be replaced every 20k miles.

Just passing on this information.

Cheers all.