SleepRM3

Besides 1999, which 996 model years had limited slip differentials? In doing some research, it seems after 2000 (or 2001?), LSD was removed from the options list once PSM became standard on the 996?

Does the current 997 series 911 have LSD--the Cayman and Boxster Ses do NOT?

Short of cost--I can't understand why Porsche does not include a mechanical limited slip differential with their venerable 911 models--my humble E36 M3/4-door comes standard with a limited slip diff (as do all M cars)??!!

I want LSD because I do PCA DEs (currently a CIR PCA and MOR PCA DE instructor).

Thanks in advance.

nick49

I'm no expert here but my thoughts are that ABD Active Brake Differential took its place and is no longer needed. I believe the ABD uses the ABS braking system to sense wheel slippage and brake that wheel which essentially does the same thing as LSD without using mechanical clutches in the diff.

1999Porsche911

Active braking systems DO NOT do the same thing as LSD, but do just the opposite. It slows the wheel(s) down to keep them in sync. With active braking systems, the spinning wheel is braked while with LSD, the non moving wheel is engaged. LSD equals better performance when drive traction is at risk.

bryanMTL

2004 40th anniversary model has a LSD. I believe they are the only non-gt 996s available with a LSD

1999Porsche911

It was an option on the 1999.

P-Car fanatic

I have TC, LSD and ABD on my 99

Only downside is that I don;t do much to take advantage of it

Ed Newman

LSD is a wear item and requires maintenace about once a year on a track car or every 2-3 on a street car.

SleepRM3

The 40th Annie will be tough to find at a reasonable market price. Thanks for the tip. Interesting the 40th Annie uses PSM and a mechanical limited slip?
Brakes are also wear items, and the rear brakes will get worn much faster with ABD engaged often. It's a copout for Porsche--for whom "there is no substitute"--to brake individual L and R rear wheels--a la ABD--to serve as a substitute for a mechanical limited slip diff. Sounds like I'll be shopping for a '99--the "driver's 996"?

Russ Murphy

While I do have a "driver's 996" myself, I'm not sure I'd agree with your assessment. Put me (or you) in my car and then in a 997 and I'm quite sure the lap times would be better in the 997. It's a better car with or without a lsd.

1999Porsche911

Turn off the 997's PSAM and other electronic "sissy" controls and the same car with LSD is much more controlable around the track and will produce better times. For people who cannot handle competitive speeds around the track, it wouldn't matter.

SleepRM3

I've driven a student's '99 996 to its limit potential--it was downright scary and fun at the same time. My BMW E36 M3/4-door's perfect 50/50 fr/rr weight distribution is forgiving at the limit while my student's 996 was not nearly so. It's an eery feeling to feel the back end rotating so much in his '99 996--my student tried to duplicate my speeds in his car, but we ended up in the weeds--no harm no foul. Electronic aids kill power delivery, and brake individual wheels for the car to regain traction (which again is slower if the driver is trying to adjust the car's cornering attitude with the gas pedal).

LVDell

So what exactly are you saying Sleeper?

SleepRM3

Electronic aids help inexperienced drivers, but hinder experienced drivers. With my student's '99 996, PSM would have kept him out of the weeds, but I would not have had as much fun rotating the back end of his car at full speed LOL I noticed the 2000 996es had LSD as optional but also have traction control as standard? The 2000 sounds like a winner?!

LVDell

Ah....much more understanding when it is sweet and simple

SleepRM3

Cool avatar--what track?