Dilberto

My 2005 Cayenne S with 65,300 miles has developed a sound under the shifter. The noise is like loose, rattling plastic, at highway speeds off-throttle. Once I apply gas, the sound dissipates. However, upon hard acceleration, the floorboard knocks with a pounding sound.

Before I get underneath - what am I looking for? The P!G get driven gently and I'm surprised to see this happening so early. Is the Cardan shaft replacement really necessary, or can the failing center support bearing be changed-out? TIA....

racer_65

This is what happens: the rubber inside the drive shaft mount has split.

You can just replace the mount...assuming you didn't keep driving and damaged the bearing (if it makes a chirping sounds).

Dilberto

I ordered the Driveshafts.com Carbon Fiber, one-piece unit. However, it won't be here for another 13 days. My mechanic Jimi and I was wondering what to do for my daily driver 955, in the meantime. After extensively researching the known repeated failures of the OEM Porsche center support bearing, we decided to conduct a little "experiment."

Jimi has a strong motorsports background and is great with improvising fixes on-the-fly. He was part of Ivan Stewart's Baja 500 Pit crew, during their successful 1997 season. Intending to do this "experiment" as cheaply as possible, until my carbon shaft arrives - Jimi noticed the thin, 2mm rubber membrane of the stock part was always prone to fail, given the weight of the car, the elements exposed to and torque generated....a grossly under-engineered part. He proposed to insert eight 3/8" thick Kevlar-reinforced, coolant hose pieces, cut in 1.5" slices. The hose slices were to make up for the torn rubber of the existing stock center support bearing assembly. Once the old rubber was trimmed out - Jimi carefully inserted the hose slices in a circular fashion. He stated the eight pieces will effectively center the Cardan Shaft, and keep it there. He then zip-tied each slice together, in series. Finally, he wrapped more zip ties, looping around the entire circumference of the support carrier shell. The end result looks like Cheerios circling the entire bearing support:



Jimi was able to perform this operation in 20 minutes. The total cost, including zip ties is about $12. Now came the shakedown test. We went on a 900-mile drive, from Southern CA to Northern CA Wine Country, and back. During the entire trip, there were zero vibrations present. I first thought Jimi's fix would make the center support too stiff, sending some NVH into the cabin. Nope. The P!G even did several hard 120mph pulls, on the long stretches of Interstate 5. There was nothing. The only vibrations present was from the slight steering shimmy of the worn Michelin Latitude Diamaris tires, we previously were well aware of. I was amazed at how well this performed. Jimi kept emphasizing the eight circular hose pieces create a far more robust solution, offering 5x+ the support rubber of the stock center supports. He further stated the extra length of the hose slices even facilitates the fore/aft "float" of the Cardan Shaft. This man thinks everything out! Before embarking on our test cruise - we had all four wheels lifted up and spun all wheels at a constant 3500rpm, and the shaft was dead steady. He even went on to say if two or three pieces were to suddenly come off, or even collapse...the part would still work. As a precaution - he told me at the first sign of vibration - simply pull over and tow back home, for inspection. It certainly is NOT pretty....but everything gets obscured by the carrier base cross-member.

I'm anxious to see how long this fix can work. So far so good.....STAY TUNED!!!

957Turbo

I love it! You should have patented it and charge $300 as an alternative to vertex solution! I would just have used thicker zip ties, but there is no way any of those tubes are getting out of there anyway! Please let us know how long it lasts...

Dennis C

My 2004 CS went into the shop for cardan shaft number 3 today at ~140K miles.

hahnmgh63

Great idea but I also second the zip ties as being the weak link, a more permanent fixing and you've got a great thing going there as your shakedown cruise suggests.
Also, give us feedback on the Driveshafts.com one-piece carbon fiber driveshaft. I know Lindsey Racing is selling these and I have respect for the Lindsey brothers. There have been a lot of Naysayers on here about the one-piece driveshaft so some feedback would be good.

deilenberger

That's a WONDERFUL McGuiver! I love it. I almost feel like doing it to mine before the rubber mount craps out. And I think the tie-wraps will be just fine. There is no real force pulling on them so they are not likely to fail, they just serve to hold the tubing sections in place.

I think this post deserves post of the year/month/decade on how to save money on your Cayenne, and come up with a superior "fix"..

User 4221

Wow! Very clever. You could also use fuel injection hose.

Will keep this in mind going forward. It would be a good roadside fix in case the bearing crapped out while in the middle of nowhere.

deilenberger

Meanwhile - I'm rummaging in the garage to find suitable rubber tubing and tie-wraps to toss in the spare tire well along side the spare bearing assembly I have in there.. (and the spare coil..)

hahnmgh63

I would think that metal/steel re-inforced fuel injection hose would be the best. Although I'm still interested in hearing more about the Lindsey Racing / Driveshafts.com Carbon Fiber driveshaft.

Dilberto

Jimi did this fix on a Nissan 4x4 truck, and he said it lasted almost 4 years, until the truck was crashed in a desert race. I'm curious to see its longevity in a vehicle of the Cayenne's caliber.

Jochy

Very crafty and low cash solution!
If I would rely on this solution for long term, would absolutely use stainless steel zip ties.
For approx 13 days of use...plastic ties the way to go.

Jimmy: join rennlist club! sure you will be a great addition to this community with your experience in the battlefield !

Lery

that is such an awesome idea!!!
I Did my coolant pipes last year on September and also need to submit my application for reimbursement for a law suit against Porsche for them. They already won the case. Has anyone here gotten money back already?

rymo926

I Jimi my shaft about a month ago and holding up. Check on it twice. Every other week when I wash the pig. Thanks for the tip!

Dilberto

I now have 9400 miles on the Jimi'd Cardan Shaft. It works too well....I returned the carbon driveshaft last week.