How do I tell if my differential is limited slip?

[blackout881]

This might be a dumb question but im looking to change my rear differential oil myself, i understand how to do it just want to know if i have to add the friction modifier or not. My truck is a 04 EB 4x4 4.0 with 93k, Not sure how to tell if its limited slip or not? Not too knowledgeable on that front. Thanks guys

 

[Ronin8002]

Look at the axle code in the driver's door sill or on the tag that's mounted to the diff cover. It should have an "L" in the code if your rear axle is limited slip.

another way to check is jack up the rear end of the truck so both wheels are off the ground and put the trans in neutral. spin one of the tires....if the other one spins in the opposite direction then you have an open diff, if it spins the same direction you have a limited slip.