2007-2009 Honda TRX300EX TRX300X service manual, Page 267Get this manual
REAR WHEELSUSPENSION Install the snap ring into the bearing holder groove with the "OUT SIDEmark facing outApply grease to new dust seal lips and install them into the bearing holder until they are flush with the holder end surfacesTOOLS: Driver Oil seal driver attachment Pilot,40 mm 07749-0010000 07965-SA00600 07746-0040900
Coat new -ring with engine oil and install it between the sprocket flange and axle