Matt K.-is that up & down movement,or side to side on the stubshaft? ive takin'em out of 12's & 14's but found it was better to leave them in on the 16's.you can try to leave them out if you want,but run it before you put it back in(if it dont work itill save you alot of work)is this tractor a 1650? if so,make sure your engine mounts(rubber) are good. also check the driveshaft. T