I just recently brought a 3 inch body lift kit ( 3'' coil spring spacer; 3'' rear blocks) after installing these components, is it possible to fit 375/75/16's without rubbing?
If not what would be the maximum tire size i can use with no rubbing?

 

Hopefully you bought after market control arms too or you'll never get it aligned and have terrible ball joint angles.

And there is no way your clearing a 38x14.50 on 6" of lift on a 2wd. Better go up to about 12" if you wanna clear those.

Those most you'll clear is a 315/75r16 or a 35x12.50 with some rubbing and some trimming dependent on the wheel.

Without rubbing maybe like a 295/75r16 or a 305/75r16. Which are in the 33-34x12ish range.