check your bearings on the auger pan drive shaft,the bearings in the oscilating arm, and the bearing where the front arm pivots. check sn. with parts might need to slow down drive. they sped some up in 2100 now they are slowed back down. on later 2300. and be sure you tighten bushings in the middle. also make sure shaft is not twisted.on the drive so both sides are even. good luck.