BrendonSF

The concept of "lifetime fluid" is not specific to Porsche, as many other manufacturers use it as well. Though many have started moving away from it in recent years. In the interest of simplifying the maintenance schedule of the vehicle, the fluid is "rated" to perform for the life of the component. But in many cases lifetime can be defined as 100k or 150k miles. For example, in my older BMWs the transmission fluid was considered lifetime, and the rated life of the tranny was 100k. It however could go well beyond that, and a fluid change would help to that end. The reality is that in nearly all cases fluid at 80k miles is not going to be offering the same level of protection/performance as new.

deilenberger

There is absolutely no explanation or reasons given. Usually, they say this sort of thing to minimize future ownership costs so people buy the thing and get it out of inventory for them. When BMW started including 2 then later 3 years full maintenance in the price of the car - it was amazing how many parts became "lifetime fluid" overnight. Without any actual engineering change to the parts. Call me jaded, but I suspect they're watching their bottom dollar - profit.

Shred

Yeah, they also said the IMS was lifetime thing which couldn't be replaced hahaha

twodollardoug

I wonder how motorcycle engine oil would work in the transfer case? Motorcycles use wet clutches just like our transfer cases do. Or maybe the hypoid gear oil we use in our aircooled gearboxs? I might do some experimenting.

efoss99

My TC was replaced on 2016 CS at 10,000 miles m/l.

deilenberger

And you filled in the survey?

deilenberger

You might end up destroying the transfer case with that experimenting, especially with hypoid oil. The transfer case clutch is much closer in composition to an automatic transmission clutch pack - which is why ATF is basically what's used in it. Keep us in mind when you do your experiments - lets us know the results.

karlusmagnus

I didn't find an answer to this ... and in same situation ...when looking at used Cayenne's at a non-Porsche dealer, is there a resource at PCNA to check VIN records and see if TC has been replaced for that particular VIN? A car fax does not show much ... Thanks

garrett376

A dealer or any person with a PIWIS can look at the All-wheel drive control unit's "A50_Mileage - distance travelled, transfer gear" value to see how long it's been in the car. If it matches your overall mileage, it's original.

Doesn't matter much, since some fail frequently, others may not. There are numerous compounding variables here. Plus, the rebuild's parts are not expensive enough to pass on a vehicle you're otherwise interested in.

r553

A non-electronic method would be to look on the firewall to see the new vent tube added when the TC is replaced on warranty.....

garrett376

Except there were many transfer cases replaced before the vent line was implemented. Mine is one of those.

Mike41

Anybody have a photo of where this vent tube is in the firewall so I could ID it?

vtwinsports

Hello,
Second owner of a '13 CTT. Transfer case issue just recently diagnosed with 94834 miles. Changed out the fluid-Ravenol-(while warranty company shuffles their feet and Porsche refuses to open transfer case to 'prove' cause of failure to warranty company.) Still going through 'learning' mode, but ~99.9% of issue is gone. Full throttle with no hesitation or hiccups. No one (else) can feel the issue at all. ( I reserve the .01% for stronger than normal downshifts, especially in Sport mode.)

KWP1911

I have a '14 Platinum with 67K miles. I'm starting to feel some jerkiness in 3 and 4th gear. I'm going to change the fluid and add the friction modifier first to see if it helps.

twodollardoug

That sounds like the best first move.