Hi I have a level 37 sith lord (level 15 consular) (level 22 sith lord) and I have yet to recieve force crush, I have crush opposition 5 but that seems to be different, before I level up further I was wondering if there was something I had to do in order to get force crush if so, what?

you get force crush when you visit dantooine the 2nd time, kreia does her thing and leaves and you get force crush.

will I still get it if Im already level 40?

You'll get it automatically as a free power when Kreia takes you to Dantooine later in the game, even if you're lvl 50.

Force Crush is friggin baaaad.