Just purchased a D7-17A14949, under load in first gear when it gets close to stalling out it will pop out of gear, I assume this means a transmission job. Its become so worn that it wont hold the gear and pushes out. I guess Im looking for someone to confirm that, or correct me, its one of those times that I dont think Im wrong.

Might want to check out wear and condition of lock out mechanism before going in:)

Yes, what OM said.

I was in your shoes, convinced it had to be the transmission even though folks on here told me to check the interlock, and finally when I had the seat off and floor plates up, I decided to check it while it was easy. Adjusted the interlock linkage and it can't pop out now (or at least has quit doing it).

Put it in first gear, pull the clutch in and hold the clutc lever all the way back, then try to pull the shifter into neutral.

If it comes right out, there's your problem, but if it doesn't, slowly move the clutch lever forward while still keeping pressure on the shifter trying to pull it into neutral. If the shifter pops into neutral before the clutch snaps out, that isn't good because it can somehow flop around enough to get the interlock released as you are pushing down a slope/up a slope/resting your hand on it unconciously moving it forward a bit.

when its on a down hill slope it wont go into gear, does that mean anything?

You can start out with adjustments....then pull the interlock side cover and check condition of the locking plungers, springs, and detent rails, etc.

thanks, its a sweet running old girl, but needs some adjustments, makesup for it with the under carrige condition (at least 60% and clean)

Did this tractor have a hyster crane on the back?

Nope, its a cable cat with C frame, 11 ft blade and a very nice ROP on it. It has been sitting for the 20 years or so. It was sold at a debt sale and then sat for another 4-5 years. It needs a bunch of minor stuff (I hope) that a green horn like me can handle.