MChildress is right but they also came with the front bumper tow hooks and many times they came with 4. 10's...
The easiest way to tell if it has LSD is to roll the window down and make a tight turn on concrete. If you have LSD you'll hear it chewing the tread off the inside tire. So, actually having LSD is great on these trucks cause when you have the feathered front tires you just put them on the back and they get milled right off so they're smooth again!
Seriously, the back tires on an LSD-equipped truck will have a very straight-across or "flat" carcass profile...