Another rear end question

If i get stuck in the snow or mud will BOTH rear tires spin, or just the one? If both, then whats the purpose of a locker?? I have an 07 TRD Sport SR5 Prerunner. Im a little confused, if both rear wheels will turn, why would you need a locker? Be kind please, im new to all this....

 

http://auto.howstuffworks.com/differential.htm

that will help explain a little bit of how rear ends work

 

With the sport its a lsd so it tries to transfer power from the spinning wheel to the stuck one.....notice I said try because it never completely gets the job done for me. The lsd is better in rain and icey conditions..or so I'm told.

 

You have the LSD so the tire with the least traction will get most of the power, and the tire with the most traction gets some.

A locker make both back tires get 50% of the power.

Open differential give the tire with the least traction all the power.

 

they are much better at explaining lol