Originally Posted by canepole
The transmission fluid from the dealer
Did you notice if the fluid you changed was discolored or did it look the same as the lube you replaced it with? What I am getting at is if there is possible moisture contamination inside the gear case from change in temps, going from cold to warm storage or from operating in water of any kind. That in turn could change the lube to jello in cold temps and make shifting difficult as well as cause extreme wear on the parts in the transmission.
I have seen instances where the Polaris lubes have turned to sludge when exposed to any moisture. Polaris has changed its lubricants to new and improved so many times its hard to keep track. Their lubes are mediocre at best.