I have a JINMA JM248 tractor. It used to jump out of reverse. It started slowly and then got more and more often. I tried adjusting linkage. It would not go foward. Readjusted so it would go forward and had no reverse. I took the adjustable linkage off and tried to shift transfer case manually. It would not go forward or reverse.Put linkage back in and reverse worked. No forward. Tried to adjust and can not find forward or reverse. I am lost . Any ideas or suggestions greatly apprciated. Thanks.
I think you need to pull the top cover off the trans and take a look , I think I have read of problems with the shifting forks or maybe the fork pins shearing partially. also check the pins on any outside lever that goes to a shaft that is pinned. I had trouble with a pto lever like that.