2006-2008 Polaris Snowmobiles FS/FST Service Manual., Page 245Get this manual
Rear Suspension REAR SUSPENSION REMOVAL AND INSTALLATION
Removal
1234567Support the rear of the machine so that the track is off the floorLoosen the rear idler bolts, then push the rear idler shaft toward the front of the machineCarefully release the torsion spring pressure (if equipped)Remove the support from the tunnel letting the suspension carry the weight of the machineRemove the fasteners securing the skid to the tunnelPlace protective mat on the floor and tip the unit over on the left side, supporting the sled on the end of the handlebarCollapse the torque arms, and remove the suspension from the tunnel
Installation CAUTION
Always use new fasteners when securing the torque arms to the tunnelWith the unit on its left side, place the suspension in the tunnel2Align the front and rear torque arms with the tunnel mounting holesLoosely install two new fastenersNOTE: On IQ 121 and Switchback skids, verify the rear track shock pivot and brackets are rotated forward before attempting to collapse the rear torque arm34567Set the machine uprightInstall the remaining two new torque arm mounting fastenersTorque the rear suspension mounting bolts to specificationAlign the track guidesclips with the suspension railsAdjust the rear idler to achieve the correct amount of track sag1