2015 diesel - tc being replaced under CPO! No traditional symptoms other than throttle lag in first few gears. Am I 1st diesel?

 

No. There have been confirmed CD transfer case failures.

https://rennlist.com/forums/cayenne-...l#post15039192

 

An Update gents,

985.1 GTS; bought second hand with 40K KM on the clock.

well; I've done 2 TC oil changes in the past year which I could say fixed 80-90% of the TC hesitation and slippage issue; in rare occasions when the weather and car are really hot I could feel some hesitation sometimes.

Now at 70K KM the car is having a real hesitation issue; when I press the gas pedals at any gear I can hear the engine roaring but the car barely moving forward.

I will try one more oil change but this time I will siphon the TC oil while the car is hot; let it drip until the last drop; then I will fill it with LubeGuard Fixx and a new "63" OEM Oil.

this is my last shot before I go for a new TC at the dealer which will cost a fortune ($4000 for the parts only)

side note as well; I noticed that the TC mount that sits inside the cross member, is bad and need to be replaced; the upper rubber lip inside the mount is toast; I've got the part but waiting to see how the oil/additive change will go before replacing this one.

Regards,

 

Update,
2011 Cayenne S
2014-Dec 62000mi - TC was replaced by dealer
2017-Oct 100700mi - 3nd and 4rd symptom. Changed TC fluid with Porsche oil. (posted in this forum)
2019-Feb 107000mi - symptom back again from 2018 Dec, so changed TC fluid again and it is ok now.

 

Thought I'd chime in and add my experience... just had the 3rd (yes 3rd) TC replacement in my '11 CS w/ 67K. I would notice the issue most when in stat-stop highway traffic. All repairs done under warrantees happy to say, but I wasn't able to get much info from the technician or SM on whether the part has been reengineered or not. He did say that its the discs inside (much like LSD type discs) the case and told me fluid changes don't correct the issue. Another mechanic told me the TCs are too light duty for the Cayenne V6 much less the S and GTS. Maybe mine was more frequent repair since I tow a race trailer?

I've heard stories that if your Cayenne is out of warrantee some dealers will replace the TC only charging you the labor... guess you'd have to make a stink about it.

 

First and foremost, can't thank everyone enough for sharing their experiences and info here.

I have a 2014 GTS w/44k miles. Warranty ended in October. Have noticed recently a hesitation or jerkiness in lower gears as I pull away from a stop. No noises that I have noticed as of yet. Seems to shift fine and drives fine once up to speed. Reading through all of this, I'm guessing the transfer case is the issue. Anything else I can do to self diagnose? I'm going to try the fluid change either way before anything else as it sounds like it should be done no matter what.

Thanks again and I will keep everyone posted.

 

When you notice it doing this, is the car on level ground or on an incline with the front higher than the rear? If the latter, the hill-hold feature has this sensation where you have to overcome the force of the brakes that are automatically applied to prevent you from rolling backwards when you transition from the brake pedal to the accelerator. If it happens all the time and when starting off on level ground, that's a different issue.

 

Definitely level ground. Easy acceleration leaving a stop sign or light. Shift, jerk jerk, shift jerk jerk, then fine through higher gears. Feel like litlle jerky hesitations almost like tires slipping.

 

Yea, that's not good. Have you tried to change the transfer case fluid to see if it makes any difference. Sometimes the friction modifiers in the fluid wear as it gets old and can exhibit behavior similar to this. I just changed it in my 09 957 at only 35,000 miles (along with the Front & Rear Diffs) and was surprised at how dark the fluid was at that limited mileage. It didn't have any burned smell, but I also wasn't having any drivability issues, so likely it was still good, but I wanted to be proactive since it was 10 years old and I don't want to deal with a transfer case replacement on my dime if it can be avoided for $20 worth of fluid.

I used:
Transfer Case (0.9 qts): Driven AT3
Front Differential (1.1 qts): Driven LS75W-90 Gear Oil
Rear Differential (1.5 qts): Driven LS75W-90 Gear Oil

Car drives great. Still need to do the trans, but that's a more involved process than just a drain and refill, so I skipped that one for now.

 

Thanks for the info! Fluid change is my next step. My local dealer didn't have the drain/fill plugs in stock so they should have them for me by Thursday. I'll use the Porsche transfer case fluid. Hoping this really fixes the issue for $150 (I need a fluid pump too). Fingers crossed.

 

Mine happened about 8 months ago. 2013 S with 48k miles. Jerkiness and loud noise when slowly turning in parking lots.

 

Changed the transfer case oil about an hour ago. Used the Ravenol. Couldn’t have been an easier procedure. Thanks for all of the insight here! So, I’m cautiously optimistic. Just drove (to get 4 new tires!) and no jerking or slipping. It was bad this morning, now nothing! I want to drive it more as I refuse to believe with my luck that this simple fix worked.

If I could buy all of you guys a beer I would.

 

New to the forum, but wanted to let all of you know i was able to cure my hesitation/skipping from 2nd to 3rd gear doing the fluid change on the transfer case as well. It does take driving about 10-25 miles to get the oil in all the right spots and now shifts smooth! I used genuine Porsche TC fluid, but bought the Ravenol to replace and flush out the remaining oil i just bought and remaining old TC in the TC after 1500 - 2000 miles of driving. Thanks for the heads up with this post!!! Easy job. Took about 30 min!

2011 Porsche Cayenne S 93,000 miles

 

One thing a number of us over on Rennlist are trying - with some success - is the addition of a small amount (1-2Oz) of limited-slip-differential additive to the stock transfer case fluids. Some discussion of it can be found at: https://rennlist.com/forums/cayenne-...r-case-45.html (page 45 of the thread on transfer cases..)

I can report that it works. I was feeling just a bit of the lower gear shifts on my '11 CTT with the original transfer case (oil changed several times in past 50,000 miles). Without bothering to change the oil - I added about 1.5 Oz of friction modifier - and I can't feel gear changes anymore. Watching the tach when the changes take place is about the easiest way to know they actually did take place, and reveals no slippage on the engagement of a higher gear. Yesterday my wife drove the car while I was a passenger, and I was trying to feel the shift points and it was really difficult to tell when it shifted. Basically just a change in engine note - no roughness at ALL.

Based on other people having > 5,000 miles on this "fix" and the fix still working, I think it might be ready for prime time soon. Not that I'm telling you what to do. I could imagine a situation where the clutch plates are badly worn, and someone adds too much friction modifier and the plates start to slip under gear engagement/upshifts (which is why I was watching the tach.) Chances are - they could recover from that problem with another fluid change - but just a heads up that it's something I would think about.

Of course if you DO have a really bad case and you're going to be replacing it anyway (at your expense) I don't think you have anything to lose by trying this. Please do let us know here (and Rennlist maybe?) how it works out.

 

2011 CTT with PTV+ ~60k miles.

I noticed some weird thumping (like wheel rubbing against fender) when taking off from a light and turning left. No acceleration hesitation or harsh shifts though. I proceeded to change the rear differential oil with full synthetic 75W90 (whatever Wal-Mart brand) and then the Transfer Case fluid with Valvoline Max Life ATF since it's lt 71141 compatible.

The issues went away after the transfer case fluid change. Both the differential and transfer case fluid were probably the original and looked pretty black. All these fluids smell awful by the way so if you can do it outside on a flat drive way instead of your garage I recommend that.

I reused the transfer case plugs since they are pretty stupid expensive. I just cleaned them off and applied Permatex High Temp thread sealant. I only tightened the plugs by hand using a 4" allen wrench after seeing everyone crack their case. No leaks or issues with that.