The dealership will probably do this for you but when I install a new gearcase I start it on cooling muffs and then shift it 10 times between forward and reverse to let the gears mesh and get fluid moving around inside. The first hour don't exceed 3500 rpm and vary the r's. Short burst to 5000 the second hour then short burst to WOT at three hours. After 5 hours you are ready. Have fun.