[Eugene at Pelican Parts]

My SC was optioned with an LSD. You can test if yours has one by jacking up the rear and spinning a wheel. If both wheels turn in the same direction, you have limited slip. The test may not be accurate if your LSD is excessively worn.

Oh, and LSDs wear out because they use clutch disks to transmit torque. As you may know, anything that operates using friction eventually wears out.