Well it's probably a cheap strat, which means it's a generic trem, so it's probably pivoting at the front of the plate with the 6 screws. I'd apply some silicone oil there. Just dive bomb the Trem enough to fit some oil under there. Then on the back where the tension springs are, I'd silicone oil the springs. Those are the only parts connected to the guitar that I'd imagine could possibly squeak.