Bill Lehman

I've done a search and it looks like the LSD can fail early with track use but can't easily be tested. I've recently noticed the car stepping out after an upshift during aggressive acceleration. The first incident was a slightly damp road after a 2-3 shift. Yesterday after a 1-2 shift on a dry road it did the same thing. The car has 2000 track miles. Is the LSD likely shot?

CME

Bill. Sounds like the LSD is shot. Happened on my GT3 and handling was a bear. One way to test is put the rear of the car of jack stands and see how freely the rear wheels move. There is failry detailed write-up on this in the GT2 $ GT3 DIY section.
Chet

https://rennlist.com/forums/gt2-and-...d-install.html

MC 968CS

If it's anything like the GT3 lsd, they dont so much 'fail', as just wear out on track. On road they are good, but track use generally we all upgrade very quickly.

Alan C.

With 2000 track miles I'd guess the friction plates are worn out. Have you changed the trans fluid?

CME

This should be covered under the factory warranty.
Chet

Bill Lehman

I've changed the trans oil twice, previously had a tracked 987.1 and know the issue (I had a Guard LSD).

Alan C.

When my LSD goes I will put in a Guards. I've used their gears and LSD installed by Brian Copans in the past.

usctrojanGT3

Time for a Guards diff...mine was going out after about 10 track days.

noro78

I bit confused.. a presence of an LSD typically makes the car overseer under acceleration.. so I would think stepping out would indicate that it is doing its job. I maybe misunderstanding your definition of "stepping out"

James88

My thoughts as well. ^

GTgears

not on a Cayman. When we guve them a lot of lock on throttle the car pushes.

I'll be at my desk later and will find a link to a teardown article i wrote about the 987 lsds. 981 are no different and they arevway different than a gt3 lsd. They are worse.

noro78

Is it really a difference in LSDs (gt3 vs cayman) or rather how much power the engine has and its placement in the car.

GTgears

GT3: brass clutches, 15nm preload 40/60 or 28/40 ramps 3.75" clutches

Cayman/GT4: semi-metal clutches glued to plates, 0nm preload (no bell. washers at all), 22/27 ramps and 3.25" clutches

Yes, different.

GTgears

Sorry, i didnt answer your question. The difference in how a car reacts to an lsd is influenced by many things. Engine location matters. 2wd rwd fwd or awd too. The reason a Cayman doesn't drive like a 911 is midengine versus rear engine as well as the Cayman's wonky rear suspension.

sdillon

This interests me. Is the main reason to replace a GT4 LSD with yours to avoid a mechanical failure, or to achieve a different driving dynamic or behavior? Iā€™m guessing the answer is ā€œbothā€, so how would my car feel different using your LSD compared to stock in low speed corners? High speed corners? I havenā€™t thought to myself ā€œgeez, my LSD is giving upā€ but I doubt Iā€™d know how it felt.