Im running 15x8 with 3.75 backspacing and 0.25 inch spacers and clear the calipers and dont hit on any steering arms. This is with 33x12.5 tires. Granted, 3.75 will stick out a little more than 4 inch. 3.5 BS seems to be the sweet spot to not contact your brake calipers. 3.75 backspace hits the...