yo whats up here is the fiche
http://www.bikebandit.com/houseofmotorcycles/2005-polaris-atv-sportsman-500-ho-int-l-model-a05mh50ab-ac-ag-0ah-fb/o/m5539
its a 2005 polaris sportsman 500HO. The rear left tire doesnt spin... the splines in the diff are stripped. I went to transmission then gearcase and it looks to me like i need #19 but im not sure. Let me know. Thanks