I've heard there is a break in procedure for a new ring and pinion which consists of moderatly driving for 20 min, then letting the gears cool. Then driving easy for the first 200 miles. Is this needed? Would putting a locker in right away strain the gears too much as to stop them from breaking in properly? And just for clarification, a locker such as powertrax lock right, replaces the spider and side gears, right?