AWD system maintenance
07-13-2011, 07:46 PM
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AWD system maintenance
What is involved in the maintenance for the AWD system ?
Can anyone post an exploded view of the system?
Can anyone post an exploded view of the system?
Last edited by ro9beam2002; 07-14-2011 at 10:02 AM.
07-14-2011, 09:59 AM
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Jeeze, those are seemingly basic questions the answers to which are actually quite complicated. Have you searched the topics of interest? Better to enter the discussion with some foreknowledge...
A brief synopsis: Very little maintenance required past the obvious bleeding of the hydraulics (pressure accumulator, solenoid block, 4 brake calipers, clutch slave, two differential lock slaves). All can be bled with a simple pressure bleeder, and though the official Porsche method for bleeding the difflocks requires a special tool it's been confirmed you can get around this with a helper cycling the PDAS engagement switch in the cockpit ~30 times per lock.
Clutches/diffs are quite robust and complaints are rare. Change the fluids, and choose your fluids carefully.
The brainbox in the forward edge of the frunk gets wet and corrodes in some cars; def worth a look during your prepurchase inspection. No other major failures common.
Pretty bulletproof- you'll find very very few people having issues with the AWD system.
Torque IIRC is mechanically split at 37% front/63% rear, but once the computer takes over (based on wheelspin and/or yaw) the rear is fully locked and the center moves towards full lockup as well.
I have no diagram.
There are no failures which are really common, but you can read about people having trouble with the accelerometers (which are often restored by cleaning) and one of the diff lock slaves leaking. This second is the one I fear; there don't seem to be any good shadetree workarounds yet and the P-part is money.
I bought the car despite these potential shortcomings.
1. It's an all wheel drive 911; is there anything cooler?!
2. The 964 is the first real production AWD Porsche. I figure for them to take such a radical flier as bringing an AWD car to the market they had to make it very robust. Note well that the next gen C4 had a far simpler, far less expensive system installed.
A brief synopsis: Very little maintenance required past the obvious bleeding of the hydraulics (pressure accumulator, solenoid block, 4 brake calipers, clutch slave, two differential lock slaves). All can be bled with a simple pressure bleeder, and though the official Porsche method for bleeding the difflocks requires a special tool it's been confirmed you can get around this with a helper cycling the PDAS engagement switch in the cockpit ~30 times per lock.
Clutches/diffs are quite robust and complaints are rare. Change the fluids, and choose your fluids carefully.
The brainbox in the forward edge of the frunk gets wet and corrodes in some cars; def worth a look during your prepurchase inspection. No other major failures common.
Pretty bulletproof- you'll find very very few people having issues with the AWD system.
Torque IIRC is mechanically split at 37% front/63% rear, but once the computer takes over (based on wheelspin and/or yaw) the rear is fully locked and the center moves towards full lockup as well.
I have no diagram.
There are no failures which are really common, but you can read about people having trouble with the accelerometers (which are often restored by cleaning) and one of the diff lock slaves leaking. This second is the one I fear; there don't seem to be any good shadetree workarounds yet and the P-part is money.
I bought the car despite these potential shortcomings.
1. It's an all wheel drive 911; is there anything cooler?!
2. The 964 is the first real production AWD Porsche. I figure for them to take such a radical flier as bringing an AWD car to the market they had to make it very robust. Note well that the next gen C4 had a far simpler, far less expensive system installed.
Last edited by FeralComprehension; 07-14-2011 at 10:00 AM. Reason: klarity
