GF1800 Transmission issues

[dman]

Hi All, i picked up well used gf1800 a couple months ago and just got around to servicing it. The issue I am facing is no power to the main drive wheels. Everything else appears to be working as expected. It will move under it's own power when in 4x4, meaning the small turning wheels have power. However, nothing from the front. i get a good whine from it but that is it. In 2x4 it does not move at all.

The motor spins a hydro that powers the trans. It is working fine. It also spins another hydro that appears to opwerate the hydraulic cylinders (lift), which are also working fine. I checked the fluids/screen and they seem ok.

i am considering tearing the trans apart but thought I would see if you fine souls can offer any advice.

I have looked around the interwebs and can;t seem to find a similar problem. Anyone have any ideas?

thanks
dman

 

[North Idaho Wolfman]

Differential or axle issues would be my guess, Jack up the front end (yes the large tire side) and spin one tire does the other spin the opposite direction?
If it does then it's a ring gear, pinion gear or some other component that's feeding those parts.

I'm wondering what lever are you moving to disengage the 4wd?
I looked over all the prints and I don't see a set-up to disengage the 4wd?