Has anyone done this yet that will share. I have found a lot of discussion on it but no one who has actually done it, lots of people who know people who have but no one first hand.

I have just bought and yesterday eventually received the front and rear diffs from a wrecked Cayenne that was in Europe with the Advanced Off-Road package.

Two things...

1. Some say they are plug and play in early 957's, if this is true it would be brilliant but I am a little suspect because Porsche tell me it wont work (factory option only) and they wont supply the parts.
2. I am about to develop a controller for it that works independently of the existing cars systems but if someone has already done it, it would be nice just to buy theirs.

 

Why did you get a front diff too? The rear ratio different than yours?

 

2 reasons 1). I'm going to see if I can make/adapt for a front locker & 2). Yes the ratio is 4.55:1, I have 3.27:1 (I think) a big step but might be interesting :-)

 

So it is plug and play in a hardware sense. The deal is that the option was not paid for on your Cayenne when it was purchased new or as a retrofit at the dealer. Porsche has these codes called "enabling codes". The code is generated by Porsche upon recipt of payment for the feature. The code has to be entered into the PIWIS when the feature is activated/coded. There are a slew of options across all the Porsche models that will require an "enabling code" before the feature can be activated on any given model's vin.

Id be very curious as to what type of controller you come up with. It's not my wheelhouse but an Ardunio controller capable of controlling a stepper motor is what I think you will end up with. I'm very interested in this as well not only for the rear locking diff control but also as a way to control the transfer case stepper motor so I can do rear wheel only burnouts.

 

Looking at images of the Touareg transfer case, a cam rotates which looks like it has a variable control of the clutch on the cams ramp before it pulls in low range then when low range is in it turns further to fully lock up the clutch. You might be able just to interrupt the power to the motor to give you an open centre diff. You might get error codes if the ECU expects feed back on the motors position but if it is just looking at results from the wheel sensors it might be alright ?

 

Great thread and congrats on the unobtanium purchase of the diffs!

LupoSK has info to share here on this topic. We had a thread going a quite a while back about this very subject and approach. My understanding is that controllers have been built after many months of frustration trying to get the factory systems to play nice together. I'll see if I can dig up the thread...

Cheers!

 

hey guys .. we have started an instagram account to share and connect some guys that are into the cayenne off-roading world .. it’s still in early stages but there are a couple guys doing diff controls and have done it

I don’t have a way to connect you but if you look them up on insta their names are

Cayenne_ontour ( he’s building wiring looms that upgrade to the factory diff and ecu )

brysonthepainter ( has done the full conversion )

those 2 are good starts ... The group channel is cayenne_adventures if anyone interested wants to follow .. trying to post interesting products and cool adventures with cayennes

 

Thanks for the leads.

I haven't used Instagram so maybe I'm doing something wrong but I don't see any information on the controllers, is there somewhere off Instagram that I can read about what they have made.

 

Sure thing .. email or text me at dave@racecarsforyou.com or 818 747 3530

 

Thanks, email sent

 

...

 

I pulled the rear diff control motor apart today, it's a nice design. The motor is a high torque 12Vdc motor - not a stepper motor. it is probably controlled by a PWM controller to ramp up and slow down the motor speed.

The alloy housing doesn't contain any gear reduction it is 1:1, the gear is fitted directly onto the motor shaft.

In the housing is a

• PCB,
• a star shapped washer,
• an electro magnetic brake

The PCB has two switches that count the teeth on the washer as they go past so it knows how many revolutions the motor has done.

The brake holds the motor in place when it stops and releases when you want it moved.

It will be quite simple to make a crude lock/unlock controller but I'm hoping to be able to make a variable control which will require some smarts and programming. I'm not sure which way to go, maybe just to get it up and running; simple is the best. I'll have a think about it.