2004-2005 660 Yamaha Rhino Factory Service Manual, Page 112Get this manual
CHANGING THE DIFFERENTIAL GEAR OILCHECKING THE CONSTANT VELOCITY JOINT DUST BOOTS 6Fill: differential gear case
Periodic oil change 0.32 (0.28 Imp qt, 0.34 US qt) Total amount 0.33 (0.29 Imp qt, 0.35 US qt) Recommended oil SAE 80 API "GL-4" Hypoid gear oil NOTE: If gear oil is filled to the brim of the oil filler hole, oil may start leaking from the differential gear case breather hoseTherefore, check the quantity of the oil, not its levelCAUTION: Take care not to allow foreign material to enter the differential gear case7Install: oil filler plug