Porsche 997 LSD

[Pricey312]

Good evening everyone,
I have just purchased an 08 C2S with the sports suspension and 40% LSD option. I am totally naive in these matters. Is the diff a friction plate version that requires servicing?
Thanks

[braddo]

Congrats on the purchase.

Very likely to be a plate diff, that will need refreshing. That’s the boat the era’s gt3s are in and I don’t think Porsche did an ‘e-diff’ back in 2008?

It has been interesting to learn (on PH) that the biggest benefit of a LSD on a modern 911 is under heavy braking. It stops the squirm when braking really hard; 911 hasn’t really needed LSD for hard acceleration.

[Pricey312]

Thanks Braddo
Thats on the to-do list. I am buying from RSJ Sports Cars in Slough. Maybe its something they would have checked over.

[Grantstown]

Ask a friendly garage or tyre place to put it on the lift. If you turn one of the rear wheels forward, then the other should also turn forward. If the other turns back, it’s functioning as an open diff and needs rebuilding or replacing.

[Cheburator mk2]

Grantstown said:

Ask a friendly garage or tyre place to put it on the lift. If you turn one of the rear wheels forward, then the other should also turn forward. If the other turns back, it’s functioning as an open diff and needs rebuilding or replacing.

Even a totally warn out LSD won’t allow the wheels to turn in the opposite way. There is a way to check the LSD in the WSM (Work Shop Manual). Porsche’s breakaway torque for the LSD is specified to be between 15 and 30N. Car in neutral, jack up one side, remove wheel, use driveshaft lock nut to try and turn wheel with a torque wrench. Simple.

[Pricey312]

Thanks for that.
I will check it out. I may only track the car once or twice a year - is there any point in servicing the LSD?Would it be a good option to fit a quaife ATB diff when the clutch next needs doing? I gather that does not need servicing and is a permanent solution. Any advice welcome.

[ttdan]

Pricey312 said:

Thanks for that.
I will check it out. I may only track the car once or twice a year - is there any point in servicing the LSD?Would it be a good option to fit a quaife ATB diff when the clutch next needs doing? I gather that does not need servicing and is a permanent solution. Any advice welcome.

Not really. Do the check as cherburator suggests. If it foobarred then replace the plates, maybe..as others have said the LSD is less about traction and more about braking stability. If you need that ultimate stable, braking and corner entry thing sorted on the road then maybe you driving about a bit too quickly:-)

You have to be a right animal or somewhat hamfisted to break a recent 911 loose (in the dry, Carrera, Even GT3) as they are quite over tyred for the power really.

[Pricey312]

Good advice. Thanks again, everyone.