I have an 09 500HO with 660 miles on it and just changed the front and rear diff fluid..How often does it need changed??? I did it just as routine maintenance,along with new air filter,fresh motor oil&filter..DI-electric grease all my connections...Any thing else any one can think of to freshin it up..Its gonna be 70 this weekend so I plan on doin sum riddin

 

some do it per year depending onthe miles they put on, but unless if gets water in it i go w/ the manual recommended intervals. imo

 

I ususally do it every spring, unless I suspect I got some water in there, then it gets changed.

 

Change mine every Spring after the deep mud season and usually just before Winter if I hit the trails a lot over the summer. Depends on how much you have it in deeper water.