UCrazyKid

I've had my 996 now for about a month and the only thing I am truely dissapointed about is that it does not have a limited slip differential (LSD). PSM does not come close to making up for it. When trying to put powerdown in a corner and the brakes come on it is not a good feeling. I would rather modulate my traction myself with the gas pedal than have the computer step in and do it with the brakes.

What are my options? I prefer to low maintainance with a gear type LSD instead of a clutch type. I've used Torsen's (in my S2000's) and been quite happy. I see that Quaife makes one for the 996. What sort of LSD was offered in the 1999 Carrera? Should I look for one to pull out of a wrecked car? Order the part from Porsche? Part from a Turbo, GT3?

How will the LSD interact with the PSM?

How hard is the install?

Any advise would be great.
Thanks,
Andy

Oh, and Happy New Year!

wwest

A mechanical LSD would never come into play absent disabling the traction control aspects of PSM.

triode

The 40th anniversary cars came with both LSD and PSM...the PSM programming may have been different.

Adrian

Nope the PSM programming was not changed. Here is exactly what Porsche say about the LSD of the 40th straight out of the differences manual.
Ciao,
Adrian.

UCrazyKid

could the 40th Anniversary LSD be ordered directly from Porsche? or do I have to find a wrecked car? How do I get the part number?
Thanks

wwest

It would be my guess that if you're looking to a mechanical LSD for better wintertime adverse, slippery, roadbed performance then the PSM will almost always over-ride even the 40th anniversary version. But if tracking is your reason go for it...

UCrazyKid

where I live (California) there are no adverse road conditions, It is all about getting power to the wheels.

wwest

Excepting a low traction surface, with the engine in the rear and a good set of tires has anyone ever had the 996's "virtual" LSD function of PSM activate?

Not me..

lexpilot

My 1999 car has the locking differential (220 code) as well as the computerized "active brake differential" code 224, and the "traction control system" code 222. I've tried to break it loose several times and I can say that even the old 1999 technology really works.

jerler

Now that the cold temps are here and the rubber is hard, I can break the backend of my 2002 loose at will, even with the PSM.

LJpete

Turn it off. You'll feel the diff. The traction control system works fairly well on the 99's with LSD (I have the same package). They will keep you pretty far from the edge. I did find the system much more seamless and less intrusive than my BMW.

Interestingly enough, it does make a huge difference when off as you can go quite a bit quicker (on an autocross course). And use the diff to your advantage.

Pete

UCrazyKid

What I know so far...

Dealer I talked to wouldn't give me a part number.

They quoted me $5505 for the locking diff and 9 hours of labor ~$1,395.

Sounds awefully high to me. They told me that until recently Porsche would supply no part numbers and that it was just recently that they trained the mechanics to work on the 6-speed.

Pretty expensive for a gear driven LSD. I'll keep digging.

10 GT3

Is that the diff or the whole transmission? If you have a good relationship with your Porsche dealer's parts department, you can get a Porsche reman transmission for that.

wwest

If so, and traction braking doesn't become active immediately, then you have something wrong with PSM.

jerler

Wouldn't that throw a CEL?
Now I am kind of wondering. Time to find an empty parking lot and do some testing