deilenberger

"Normal" - no. Uncommon - also no. It happens. That's early failure mode stuff - where a part inside the case was machined wrong when the case was built. It's under warranty? Let the dealer put a new TC in. BTW - the usual failure mode is slipping followed by grabbing under acceleration when the transmission shifts, particularly the 2-3 and 3-4 shifts.

Dguth

Add mine to the Transfer Case issue. Mine is a 2015 Cayenne S with only 16k miles. I started feeling the jerking/slipping feeling from 2nd to 3rd. I could also hear it when turning the steering wheel slightly under low acceleration. I’ve only had it for a month. Took it to the dealer Monday and they tech immediately diagnosed it replacing the transfer case. I’m setup to get it replaced on Thursday. Ticks me off they designed these so faulty even in the newer generation 958.2s. Here’s picture of my new to me Cayenne S.

deilenberger

With the low mileage failures I don't think it's a design issue so much as an assembly/manufacturing issue. Your new case should be fine - go enjoy your Cayenne..

marinerbc

Just got my new to me 958.2 CTT CPO with 43 Km , Jan./2016 Build , shall I worry about the TC ?, asked the dealer to change the oil was told to enjoy it and not to worry.
the problem I live far away from the dealer and thinking about just pay for the oil change and get it over with.
I have no issues thus far with my short time driving it. except a small jerking down gear before stopping while in Sport+ mode
and one thing for sure unlike my old 06 CS no transmission bucking .

deilenberger

Yeah - dealers do that. Ask for the service manager - not the "Service Adviser" (who is there to sell service, but often doesn't do that very effectively.) The dealer doesn't care since the car is CPO and it would get a new TC if there were problems. More money in it for them if they change out the TC.

Since you're far from the dealer, start asking around to find the good foreign car independent in your area. Get them to change the fluid. Labor cost shouldn't be more than 30 minutes (including the time to put it on/off the lift.) Order up two new plugs for it from an on-line dealer, and a bottle of our suggested Ravenol oil. If the case ever does fail - don't mention the oil change to the dealer.. they'd likely use it to deny warranty coverage. FWIW - I was quoted several hundred dollars to have a dealer change the oil (free coffee and a carwash don't come cheap I guess..) and people have gotten quotes of up to $700 for what's basically 15 minutes worth of work.

marinerbc

That is a very good advice thank you for the encouragement, I thought about what you have proposed but got cold feet fearing of being denied coverage if something happened.
will buy two new plugs as suggested, lucky for me I know a gentlemen close by who did work on my old cayenne and he is very good.
much appreciate the help,

jtsmith18

I also asked my dealer about changing the TC fluid and they said they wouldn’t bother. I chose to heed Don’s earlier comments about what happens if it fails after warranty..the dealer won’t pick up the tab. So I went ahead and changed it but used the Porsche fluid and took photos for back-up.

deilenberger

Tell him 12 ft/lbs on the plugs (spec is 15, but I'd be cautious.. 12 will work just fine.. trust me, I slept in a Holiday Inn Express last night [not really]..)

jlusby

I would encourage anyone to make them change it before you buy it. Mine was a CPO but before I picked it up I asked them to please change and they did. I even sent them the link to this thread. I didn't get any push back whatsoever.

Kirill

Does this thing look like transfer case rebuild kit: https://www.ebay.com/itm/ATC350-450-...-/263086908030

Parts diagram: https://awd.tech/pages/pl72atc-diagram

more parts: https://awd.tech/collections/pl72-atc-vag?page=1

Not that I am planning to buy it, but if they sell it - there must be a demand for it - I guess someone figured out how to rebuild the TC

fourthirteen

Took my CPO 2013 CTT (64k miles) to Porsche dealer last week with the scraping-grinding-while-turning-sound. They implemented campaign WD31 - Re-Program Rear Diff Lock Control Unit but the noise came back within a day so i'm taking back in next week.

F1CrazyDriver

Do you have PTV Plus ? I do and i have what you're saying above. I had the differential flashed with the new update. I would say the sound is more like traction control kicking in.
I have ordered (picking up today) Porsche magical differential juice fluid. It's 1.2 qrts for the rear and .5 qrts for the front. I'm changing this weekend and i'll report back. Thus far i have done Transfer Case thinking it was that. I had no change in TC but i never had an issue with TC grind / rpms jumping.

bweSteve

I have PTV+ (along w/ PDCC) in my '12 CTT, and I've had the grinding in the left rear for quite some time now. feels like a old posi-traction gear mal-adjustment type thing. I've flushed/replaced all my Diff's oil, which had little positive affect. I'm STILL trying to figure that one out.

Also had my TC replaced under Good Will last Spring,.. which certainly did help the TC problems I was experiencing. But the grinding in the rear under slow turn conditions seems to be something completely different than TC. Although it has indeed been mistakenly discussed in "this" thread.

fourthirteen

Yeah, has PTV. And i agree that it sounds like traction control ...like clutches slipping/chattering...they think its the diff. and not the TC.

CarGuyNVA

Every 958 I've driven with the PTV+ option (including mine) has made that sound on occasion with tight, slow left turns. Mine has the new revised TC along with the other updated bits, and some time ago had the WD-31 campaign fix applied as well. It still does it on occasion though. I'm convinced it's nothing more than the locking differential clutch packs 'chattering', as I've experience numerous times in years past with various GM LSDs in F-bodies and Z06 Corvettes I've owned. Sounds and 'feels' identical. In GM's case, it's completely cured with the addition of the correct amount of GM's limited slip additive. I'm not certain if there's something that would work in Porsche's unit, but I'm sure the fluid for the PTV+ diffs has something in it that accounts for that (or is supposed to account for that anyway). I just really don't worry about it much anymore.

It's a very different symptom from a failing TC.