how can you tell when a limited slip diff is worn / not locking properly?

[Trans Am]

The diff is 3.23 ratio, has around 60k miles on it. I took the cover off when I changed the oil and the ring and pinion gears look perfect, no wear on them. oil was clean, no debris, no metal shavings on the magnet either and it looked like the cover hasnt been taken off before. I took pics, i ll post them as soon as I upload them on photobucket.

Seems like it isnt locking properly when cold, after I drive it for a while it seems ok. if I hold the brake and rev the engine so the wheels move a little it locks. It took a fair bit of abuse and sideways fun and donuts and burnouts and hard launches though lol. pretty much every time I drive it haha. But nothing outrageos, just like a trans am should be driven lol. It does lock on launches and leaves 2 tyre marks every time.
Can I check if the clutch packs are worn if I take the cover off again? how should a diff work/lock?

[Joe 1320]

By lifting one rear wheel off the ground and keeping the trans in gear (or park) , use a torque wrench to measure the force required to make that wheel turn independantly of the other wheel that is still on the ground. I cannot remember what the torque rating is supposed to be, but suffice to say if it's easy to turn..... the clutches are shot.

[Wild Willy]

Clutches? Which car (in your sig) are you referring to? What year did the F-bodies switch over to the Torsen diff?

[Joe 1320]

If I remember correct, 2001 was the switch to torsen.

[Trans Am]

Clutches? Which car (in your sig) are you referring to? What year did the F-bodies switch over to the Torsen diff?

the diff in question is a 93 t/a diff, auburn type I think.I have swapped the endine and transmission with the whole fron suspension from a 95 formula to a 93 t/a . the diff is the original 93 t/a one with about 60-70k miles on it according to the inspection logs that came with the car.