2012 Sportsman 400/500 and EFI Tractor Service Manual 9923412, Page 284Get this manual
FINAL DRIVE ADC Gearcase Piston Replacement Procedure CAUTION
This repair procedure involves the use of compressed airSafety glasses or face shield are required1Place ADC Piston Tool PA-48542 on top of the pistonUsing moderate hand pressure, hold the tool on top of the piston while using compressed air at the gearcase passage (circled) to force piston up and out of the case(See photo)
4Coat new piston and o-rings with moderate amount of white lithium grease or assembly lubeCoat the edges of the piston cavitiesInstall the inner and outer piston o-ringsOuter Inner