2005 Artic Cat trv automatic transmission issues?

Hello
I have been having some issues lately.
If the Cat is not warmed up and automatic choke is high revving. The bike rattles in high and has no power- will not move at all in High or reverse.
Once warmed up there is no problem-- until...
I start driving in high with -4 wd on-  through 12 inches snow on the lake- I lose all power- no movement at all. So I put it in low and it goes- I limp back. When I get back I put it in high and it works again. This has me worried .
Is the drive belt going?? I have been using it to plow this winter.
Appreciate your Help
Thanks
ED
 

Hi
Update

Started digging deeper. Found oil in the clutch housing. I think alot of work is needed now.
Cheers
Ed