2009-2010 Polaris RZR Factory Service Manual, Page 309Get this manual
BRAKES 8Clean the caliper body, piston, and retaining bracket with brake cleaner or alcohol2Inspect piston for nicks, scratches, pitting or wearMeasure piston diameter and replace if damaged or worn beyond service limit
NOTE: Be sure to clean seal grooves in caliper body
Caliper Inspection