Guys,
this is very odd. my 997 does not have a "locking rear axle" (limited slip diff) , yet i know i saw it on the options list.

has anyone verified that "locking rear axle" cars have a mechanical lsd ? anyone know the the specs on it ? is there any clunking when maneuvering in parking lots etc

 

pic.

 

What's wrong w your tranny?

 

Not surprisingly, what are you talking about? You "saw" it on the options list or it was an option on the VIN for your car? You took your car apart to check and it wasn't a LSD? You've hammered your car and broke the diff? The chance of a car having a locking diff and someone TAKING IT OUT is probably .0001%. The Porsche LSD doesn't make any funny noises, that I know of.

 

Is this the option you have?

220 Limited Slip Rear Differential Lock
Friction disc lock on rear axle. Pull - 22% and Push - 27%

What happened that makes you think you don't have it?

 

Did you take your car apart to see if it has an LSD?

Without even looking for it, you can tell if you have one, or if the OEM is shot (which is not that uncommon.) Lift one of the rear wheels off the ground with e-brake off. Put the transmission in neutral while the other wheel on the ground.

If you can spin the lifted wheel without much resistance, either you don't have an LSD, or your LSD is done.

As far as noise is concerned, a working LSD will make some noise when you go full lock left or right, and move the car forward a bit. You should hear the LSD and feel the wheels in the rear "chugging".

If there is no noise, and your wheel spins freely in the above test, either the LSD is dead, or you have an open diff.

 

Stock LSD's break fairly often. I know a 997 guy who has had his replaced by Porshe twice under warranty. When it broke the third time he went aftermarket. No more problems.

 

stock 997 lsd's are WEAK.
if youre making any sort of power, your lsd will go bye bye.

i took out the tranny because i put a gt2rs gearbox in my car with a REAL cup car LSD.
all clutch type LSD's will make a clunking noise.

the car was advertised with an LSD, i need to get a printout of the actual window sticker to confirm.

i just cant understand how a car with ccb's, sport chrono etc wouldnt have a $500 locking diff.

 

our 997 gearbox.

 

I just realized that were talking Turbos, not GT2s. The rear wheel spinning trick won't work.

 

sure it will
front drive gets no power or drag resistance when the car is off.
pretty sweet.
the 997 awd is worlds better than the 996 "awd"

 

First the TT use a electric clutch? I thought it is engaged when the car is "off."

 

bbywu,
im gonna have ur gearbox in my car man !! a girls version of a gt2 lol

nope its disengaged when the car is off.

 

Subscribing and confused. From what I undestand axle diff lock and LSD are two different things. How does the axle diff lock work in the Turbo versus a true mechanical LSD? Is it managed via PTM

 

^Tom, i dont know.
i thought a "locking rear diff" and an LSD were the same thing ???
i have a new diff going in anyway (stock lsd's can fail in ONE track day).
i am reselling the entire 997 drivetrain. thats why i was so curious about a "locking rear diff".