John Deere 112L Transmission fluid

[jakesmurray]

I took the drain bolt out of the bottom of the transmission and drained out the fluid. The fluid was red colored. After I was done, I opened the fill cap, and it was still full! Is this the right fill tube or is there another one (it is under the seat)? I am thinking that the drain hole is plugged, or I need to tip the mower backwards to get all of the fluid out. Thanks for any help.