Tru-Trac

I have a 1988 Jeep XJ with a Dana 35. I'm wondering if there is a way to tell by looking if it has a tru-trac limited slip differential ? Thank you assgas:

The trac-lock was installed by the factory on some models. The tru-trac is more of an aftermarket product. If you are not the original owner, it's possible that a previous owner might have installed one. You have to open the pumpkin to see what type of traction device you have.
there is a way of knowing whether you have an open or closed differential. Lift the rear tires off of the ground. If one tire spins one direction while the other tire spins in the opposite direction you have an open diff.