how can you tell if your transmission has lsd or not???

I have been told that if you look through the axle holes and there isnt a round bar in side its lsd

but i also have been told that if you jack it up and spin one wheel and the other wheel spins the oposite direction that it is lsd.

my tranny has the rod thing in the axle hole but if you spin one wheel the other wheel spins the opposite way. So do I have lsd or not

 

just do a burnout and see if you have 2 tire marks or just 1