2004-2005 660 Yamaha Rhino Factory Service Manual, Page 326Get this manual
FRONT AND REAR BRAKES WARNING
Use only the designated quality brake fluid: other brake fluids may deteriorate the rubber seals, causing leakage and poor brake performance Refill with the same type of brake fluid: mixing brake fluids may result in harmful chemical reaction and lead to poor brake performance Be careful that water does not enter the master cylinder when refillingWater will significantly lower the boiling point of the brake fluid and may result in vapor lock3Air bleed: brake system Refer to "BLEEDING THE HYDRAULIC BRAKE SYSTEM" in chapter 34Check: brake fluid level Brake fluid level is below the "MIN" level line Add the recommended brake fluid to the proper levelRefer to "CHECKING THE BRAKE FLUID LEVEL" in chapter 3