Stuck shift lever on a new Troybilt Big red.

The shift lever was getting progressively harder to shift. Now it will not shift at all nor can it be shifted to reverse. I checked the drive belt. It's loose. The handle is frozen. New tiller, starts OK, can be pushed OK. The hi and lo speed lever also works.

Have a real good look at the shafts.
The bushes wear then make the gears hard to shift.