2000-2003 Honda TRX350 Rancher factory service manual, Page 283Get this manual
REAR DRIVING MECHANISM
REAR AXLE INSTALLATION
Apply molybdenum disulfide grease to the center spline of the axleInstall the axle into the final gear case from right side until it is fully seated(SPLINE)
Coat new O-ring with grease and install it into the gear case grooveInstall the side collar onto the axle with the tapered side facing inward