MX-8 Elite diagnosis help?

I've had this thing for a few years. Pretty happy with it. It needs treads every season but other than that I leave it in year-round and only have the occasional leaf clogs in the motor. The leaf canister saves me from filter cleanings too. Right now it wont move. I pulled it up, keeping it under water and the motor and spinning cleaners are moving fine. The treads move super slow when I am suspending the cleaner but not when sitting on the pool floor. Could there be a problem with the two gear boxes on each end? I still havent pulled the motor out to see what the motor drive gears look like. I watched a few videos so I am pretty familiar with out it all works. I was hoping I could find some advice on here before just throwing parts at it or *gasp* taking it to the pool store.

Also, are you guys leaving in cleaners year round? I do, and I'm sure I shorten the life, but I dont cover my pool and it saves me from scooping debris off the floor every week. I have new plaster from this summer too so I really dont want anything to sit on the floor too long.