It is not mechanical. It is electronic and works with the ABS. If you have any ABS faults it won't work.
In general it works very well. But does take a little tire spin to work it.
Now a 2010 should have it, I think. I know the early years ('05ish) it was an option. Slowly over the years it went from an option to standard more and more. Not sure what year it was standard on everything. If you have the window sticker and it states something like BLSD or ALSD or traction package you have it. The B in front of the LSD is "Brake" and the A is "Active". Same thing, different marketing person wrote it.
So what trim level do you have? How much spin did you give it? Do you have any warning lights light up on the dash?