Anyone interested in buying a Porsche Cayenne who’s been researching their purchase via forums is forgiven for massive paranoia regarding propshaft failures. The truth is that propshaft or cardan shaft failure is going to happen to any Cayenne you buy. Propshafts or driveshafts are maintenance items on any vehicle: especially 2-tonne 4wd SUVs.
Porsche Cayenne Centre Bearing Mount
Prime suspect of a Cayenne propshaft issue is the centre bearing mount. The bearing supporting the CV joint in the middle of the two-piece propshaft is mounted in rubber. Like all rubber mountings, it eventually wears out. The vibration from a failing centre CV joint will often kill the bearing. It is under a heavy 4wd car in all weathers, so do not be surprised about this: the part cannot be expected to last indefinitely.
I just had to sort this ‘cardan shaft’ centre bearing mount failure on my Cayenne S. The centre bearing mount failed two weeks ago and I have been driving it around ever since, in the process of sorting it out to my satisfaction. If you’re easy on the throttle you can keep driving it a bit. I am now on my second shaft this week: a brand new OEM GKN Spidan propshaft.
I went a slightly long way around this issue, as the usual suppliers wanted the original prop shaft in exchange and I wanted to keep it for rebuild. I bought a recon propshaft from eBay and fitted that to the car, but as soon as I drove it it was obviously wrong. So I ordered a new shaft and fitted that last Thursday morning. I’ve got a miniscule vibration above 80 mph: more a sound than a sensation, but it still needs sorting out.
Porsche Cayenne Cardan Shaft Propshaft
My old shaft had apparently been on there for 135k miles. The car has been maintained by a Worcester specialist since 60k miles and we know they have never done it. I very much doubt that it had ever been apart: it took me ages to split the shaft off the diff input flange. In the few days I ran it with a less than perfect centre bearing mount, the centre CV joint was seizing until it warmed up, which could easily have caused the rubber mount to fail.
Taking the second (supposedly recon) propshaft off the Cayenne, no doubt the centre bearing has been replaced on this, but the centre CV joint is just like my own one: sticky and recalcitrant. The new shaft feels totally different.
Speaking to a few propshaft experts this week, all agree that the problem is tied to the centre CV joint. The complete shaft has three CV joints for maximum smoothness, but the centre one takes most abuse, is the most exposed and will eventually seize up and fail. That wears out the rubber bearing mount, but most people just swap the bearing and don’t sort the CV, which causes the same problem soon after.
Although I have a new shaft on the Cayenne now, I plan to send my old shaft to a specialist who was very helpful this week and obviously knows his stuff. He will refurbish it before balancing at the highest RPM. I plan to refit that to the vehicle in due course and see where we go from there. This is a key part of the transmission, so I want it perfect.
A Cardan Shaft is a propshaft is a driveshaft. The original concept to adapt ancient Chinese gimbals into a universal joint to use in transmitting power came from the Italian mathematician, Girolamo Cardano, in 1545. It’s been called a Cardan Shaft in mainland Europe since becoming common in the early 1900s. It’s a prop shaft/propellor shaft here in England, thanks to common use in the industrial revolution. A driveshaft is the same thing, normally smaller.
So, don’t think Cardan Shaft is Porsche’s fancy name for this. Cardan shaft, prop shaft, drive shaft: same thing.