Spastik monkey

I just bought a used 2004 Porsche Cayenne today with 84,000 miles on it I'm having an issue driving at home.it seems like the transfer case or the differential keeps locking up and then unlocking. It makes a thumping sound in the front end but goes away when I hit the brakes.the sound will persist for about 5 minutes then the light will come on saying Lock over loaded and the sound will go away. What do I do? I had the PPI done at RUF in dallas.

seafeye

Before you rule out the transfer case.
Change the oil in it. Very very easy to do. Pull the plug. Drain the oil. Then fill again with proper gear oil.
I believe most transfer case's were changed not because the actual case was bad but the electric motor didn't work properly. Actually there is a sensor in the motor that i believe is the issue. (Made in USA).
Replace the motor with a 2008 or newer model. (Made in Germany).

You should be able to buy the electric motor for less than $100 used from a wrecked car.

Spastik monkey

What fluid does it take?

hahnmgh63

Transfer case is a synthetic ATF meeting Esso spec LT71141. Most of the better quality synthetic ATF's meet this spec such as Redline D4. Look for the spec on the label or check the manufacturers website. The newest thinner ATF's are a different spec.
Also, there was a bulletin about changing out the motor and software (Transfer case module) because of problems. It was due to a thump being heard. TSB 2/06 3965. The newer control unit software was standard as of 24 Oct 2005 per the TSB. Your old control unit should be part 95561802304, the newer one should be 95561802305. $335 new from Sonnen Porsche.

Spastik monkey

So not a recall? Just a tsb?

hahnmgh63

Yea, not a recall. Here is the motor and control unit update from Suncoast Porsche but I think Sonnen Porsche or Sunset Porsche will beat their price. Or as mentioned, if you can find a late '05 to around 2010 in a wrecking yard you will be set for much less money.

Spastik monkey

Well I did make it home. The thumping seemed to get worse right before the Lock Overload message would pop up, then it would immediately go away

Orantes

Have you checked your error codes? This has recently happened to my 04 S and has now gotten worse. I will run my Durometric and see what codes I get....

hahnmgh63

The Suncoast Porsche website says the new PTM transfer motor and Control module are for "Display in instrument cluster: "All-wheel drive system defective" - For fault code 2033, 2039, 2041, or 2042 in transfer gear control unit.".

Spastik monkey

Mine doesn't show "all wheel drive defective". It shows "lock overloaded"

mcbit

New one on me, your's seems to be the the only Cayenne thread on the internet with the phrase "lock overload" in it.

Spastik monkey

I'll post a pic next time it does it

Spastik monkey

Technician says the issue is the Tires are 2 different brands. Could this actually be the whole issue?

Km1.8t

With the Cayenne, anything is possible.

seafeye

I believe so. I have seen strange issues with just worn tires. Personally i'd like all 4 tires to match.