All "SE" trucks have the LS as a standard option. In the "XE" you had to buy that option. I believe that in the Dessert Runner it too came with LSD.
The LSD in my SE breaks away real easy. Meaning if you step on it in the rain you will easily get it out of LS and the truck will fish tail. Same thing for snow.
One way to figure out if you have LSD is to look at the pumpkin in the rear. There will be an orange sticker on it. With mine it had some deep road debris and I had to scrap off a lot of crap to find it. Also you can look at the door jamb (as others have said). Also, if those fails you can lift your rear end and then put your tuck into "N" - BE EXTREMELY CAREFUL. Spin the back wheels and if both move in the same direction then you LSD.
2003 silver CC LB V6 SE non-s, leather, SPAL e-fan controller, nismo wheels, bed extender, alarm, e-fan, Nismo CAI, sunroof, nerf bars, knock sensor mod, interior courtesy lights, Rockford Fosgate Audio, oem trailer harness, Nismo CAT-Back, *My Best truck mod
* children seats in rear.
My Write ups - e-fan
, Nismo - CAI
,Disable auto AC w/defrost
,How to work your 4x4
Good Links -
Distributor Bearing Fix
, Nissan Frontier Specs All Years
,Intake Manifold Removal/