Hello to everyone on here. Im a loooooooooonnnnnggggg time lurker of this forum. Helped me with my knowledge for Porsches and other things. Finally had to make an account cause i need all your help. I know where all mechanics and even porsche technicians have failed this forum might be able to help me out. Here goes....
back in december of last year I got my wife a new to us 2014 porsche cayenne 4.8 with 99k miles ( I got it from the auction so I got a sweet deal compared to the prices right now) . Fully loaded with all the bells and whistles. My wife was pregnant with our first child at the time.So right after i got it I Changed front diff , transfer case and rear diff fluid and engine oil right away ( I do most maintenance work myself on my cars cuz i have access to garage lift and tools. I bought the fluid from porsche dealership) . We took trips to new Hampshire and New york drove like a champ. In march at around 103k miles my wife was backing up her parking spot and car only reversed like 5ft and came to an abrupt stop. She drove forward and it went fine and then she put it in reverse and it again drive back 5 ft and stop at the exact spot. She did that a couple times and after that gave it a little more gas while reversing heard a sound from the bottom and then drove fine. I drove it when i came home that evening and the car drove fine. I told her maybe there was something in the driveway. ( There wasnt anything in the driveway. our driveway is clean) One month goes by no issues. Then in April I go to Home Depot and while leaving Home Depot parking Lot it got 5ft forwards and got stuck again. In reverse its fine but when i put it in D it drives 5ft and stops. I reverse it back into a parking spot and shut off the car and I wait. I start and it drives but there is a faint noise coming from the bottom. Since there is an extended warranty on the transfer case and me assuming its the transfer case I make an appointment with my local Porsche Dealer. I drove with the porsche technician and he heard the noise and since the transfer case is covered under warranty it wouldnt hurt to change the transfer case since they go bad all the time. They take a month to change the transfer case and call me to pick it up. I send my brother ( I was in the hospital welcoming our beautiful daughter) to return the loaner ( a 2021 Macan with the pdk transmission- I had my fun with the Macan) . He picks it up and brings it home. A few days i have to go pick up some diapers I take the porsche and the noise is still present. I am not even worried about it cuz I havent slept at all and just wanted to get back home to sleep. it didnt get driven much I just drove it to the grocery store and the pharmacy right down the street. A couple of weeks later the noise gets louder and an all wheel drive system fault error pops up. I was kinda glad that there is an error code to pin point the problem. Take it to the porsche dealership again. After a couple days they call me and tell me that the new transfer case they just installed a month ago was faulty and they will order a new transfer case. They install a new transfer case and the all wheel drive system fault is still there. The Service advisor calls me and says that they gonna have to dig deeper and inspect the problem and the technician wants to change the front diff and rear diff for a tune of $980 and see if they can find any metal shaving in there to determine the error. I told them to give me back the car. I can change the diff fluid myself and check for contamination even send it testing. I got the car back. A couple of days of my wife driving our daughter to her appointments she goes to cvs to pick up some meds and the car just stopped in the middle of the drive thru . Im at work she calls and i tell her to just tow it to my mechanics garage. This mechanic is a really good friend of mine. And he is a smart mechanic. He works on all european cars and himself owns a couple of 911( Both 996) He never charges me for labor. I do a lot of his construction work for free and he doesnt charge me when i do need his help. So he texts me a picture of my front differential ( pic attached) and calls me and tells me that maybe i didnt change the front differential right. I dont think so but i dont give it attention. Atleast we found the issue I order a used front differential with the correct gear ratio. He installs it. I tell him to drive a couple of weeks since my wife and daughter are in chicago visiting her parents. He calls me a couple of days and tells me that he was stopped at a red light and the car wouldnt move in D. I tell him this has happened before. He tells me something else had caused the front diff to blow up. He is gonna need more time with it. He is low on staff ( nothing new) and backed up with work. But he will take a look at it when he finds time. Im wondering if something like this has happened to anyone. Any help is appreciated. Im gonna add pics from my phone later

 

Shameless Bump

 

Any body??? Still clueless and no one can figure it out including porshe dealer.

 

hey man i know this is 2 years late, but i literally just went thru EXACTLY what you stated, except my front diff's symptoms were different, but doesnt matter because at the end i need a new front diff just like you did. I bought a 2013 Cayenne S with 114k miles on it, and immedietly changed the front and rear diff, and transfer case fluids. Exactly 5 days after changing the fluid i start hearing a weird pulsing noise that sounds like its coming from the front right wheel. Nothing i do is changing this noise it was driving me crazy. Anyways it started getting louder so we put the cayenne on a lift, and put it in Drive and immediately found the noise coming from the front diff where the propellor shaft connects. Video of the day we found the noise below, it was a few days ago. Now im searching for a used front diff to purchase, and i keep thinking that the fluid change is what caused it to fail, but everyone keeps telling me its a myth/coincidence and that these front diffs fail all the time on the 958.1 V8 Cayennes. It was just too much of a coincidence/perfect timing for me to believe that if i didnt flush the fluid it still would have failed. Anyways, videos below, and would love to hear what ended up happening with your cayenne 2 years ago.



Its also super whiney when accelerating from stand still. you can hear it in the first video above, as soon as the wheels start turning you hear that gear whine. This is what it sounds like when in the car...

 

Not great, hopefully there are some improvements in 958.2 models. I'm going to change my 2016 base fluid this weekend. I'm really surprised it only takes .5 L, much less than my 957. I'm going to rotate the wheels after filling to see if there are any air pockets.

Mark

 

I think it’s mainly a problem with the 958.1 v8 models.