JD4200 will not move in B or C but will in A

[sleeperman]

I went and put out a bale of hay today and on the way home I was in C gear going down the road and the tractor started acting like someone was puting on the brakes and soon after that the back tires locked up and would not move. If the forward pedel is pushed it will not move and if push hard enought it will kill the motor but the motor will start backup. It will not move in B and C like the emergancy brake is on all the way but in A it will move like nothing is wrong. Can somebody give me an idea of what is wrong with it? thanks

 

[kennyd]

Welcome to TBN

It is not uncommon for the brake shafts to seize where they enter the rear hubs, there are also springs (#18) that help return them that are known for breaking.