If you are changing from 375-50 to 275-60 this will change the pinion angle . Too much angle up or down will bind the u-joint and cause premature wear or failure . Also , the ride height must be set before the pinion angle must be set . Changing ride height (or tire size ) changes pinion angle . Set that first and then measure the pinion angle . FYI pinion snubbers work , no good on the street , though .
