I had recently purchased a 2021 XP1000 4 seater with all the bells and whistles. Cab heater, the works.... so it overheated twice with under a 100 miles on it. dealer loaded it up and took it back and thought it had an air bubble due to heater install.....it overheated the second time and he came and got it and worked on it to no avail and afterwards got in touch with Polaris engineers.....turns out the accessory dept at polaris made changes to the heater kit bracket at the thermostat that would not let the "plate" open properly. Solution recommended by the polaris engineer was to drill two 1/8'' holes in the plate which allows the fluid to flow properly. Engineer told my dealer that they are seeing this more on the XP models for whatever reasons. Just wanted to put this out there is someone is experiencing the same issue with no solution yet. Have a great day.