2008 Polaris Sportsman 500 EFI/X2/Touring/500 H.O. Service Manual, Page 292Get this manual
TRANSMISSION 12Install the rear drive differential and drive chain, following these precautions: The case half rear output seal should be removed prior to installation of the differential, as seal damage can occur with seal installed due to the angle of entry X2 and TouringInstall the differential sliding geardog onto the shift fork arms at the same time the silent chain is installed The differential gear bearing may be lightly tapped into placeThe case half seal can be installed once the assembly is in placeSpring Leg Forward Tensioner AssemblyTop View
Tensioner
Lock Cam
13Tensioner Installation: NOTE: Case-halve mating may be difficult due to tensioner