Time to add The Greaser ! With a new bearing of course ! Well made unit , easy to install and pump out any crud that makes it way in. Like I mentioned before I have the prototype with over 1,200mi no issues.
also check ski alignment , some trails can be ruff and they can put them out of alignment. Every couple years I do a chaincase clean and flush , and engine flush with engine oil , not engine flush stuff ! Drain , pull tube from lower tank , clean , add oil ,run engine for a few miles , drain and repeat . I do it 3 times , it just gets the dirty out . You can just get cheaper thin oil if you do and add your brand of good oil and filter when finished . Also time to drain brake fluid , flush , bleed and add , coolant also . This is just me , and fluids do where out like everything in life .