Yamaha says they've devised a minimal maintenance brake for the rear axle of the Kodiak...
http://www.atv.com/manufacturers/yamaha/2016-yamaha-kodiak-700-preview-2420.htmlTo keep maintenance (and downtime) at a minimum, Yamaha outfitted the Kodiak with a new sealed rear wet brake. It lacks the same aggressive bite as the four-wheel discs on the Grizzly, but the design is basically maintenance free and Yamaha says it suffers no brake fade in water or mud.