2014 RTV 1140 Transmission not working

So I bought two 2014 RTV 1140 from a company they each had 1,100 hours. One simply will not go into any gear, but the engine runs great and so does the hydraulic dump bed. So I need to get that transmission fixed.....I have no idea what the problem could be.....the shifter is shifting/moving around, but nothing happens.....The local deal said it was making pressure, but didn't know why it would work.

The second unit, I have been using with great success, except it would only go 14mph.... I tried adjusting it like the various instructions say to and changed the oil and filters and it never made any difference....Well, two days ago, it wouldn't go into LOW gear..then the next day it wouldn't go into LOW, HIGH or REVERSE......Leaving me only Medium to operate in...and then it would thump or clunk if you took your foot off the accelerator pedal too quickly.

I took it to the dealer, today and they said the shifter is fine, but that they will have to go into the transmission and the last time they did that it cost the customer $6,000.....Mercy, that seems a little expensive, and they don't know what is wrong with it.

So now I have 2 perfectly good machines, 1,100 hrs that have useless transmissions. My question is what is the most cost effective way of getting these things operational. I need at least one running for chores this winter.

Thanks,
Sam

2014 RTV 1140 Transmission not working