Massey 1230 lost 4 wheel drive....Help????

[critterfeeder]

My Massey 1230 was working fine, I scooped a bucket of sand, put it in reverse and couldn't back out of the hole I was in because 4 wheel drive had somehow disengaged. There were no weird noises and the tractor runs fine otherwise. Linkage appears to be AOK. Tractor is only 5 yrs. Any ideas what might be wrong ????

 

[JerryG]

Was the lever hard to move? I would check to see if there is a roll pin going through the lever where it meets the transmission case. If a lever gets hard, once in a while the roll pin will shear.