oc-4g tracks locking

[Anonymous-0]

lent my tractor to a friend and he called me tonight and said it will only move forward about 10' and then the track locks up, but it will back up all day long any advice will be appreciated.
Pete

 

[Catysammy]

It is not common for rollers, idlers or a final drive to do this, but a track pin that has worked out of the rail can do this and only catch solid in one direction of travel.

 

[MANHATTAN]

the right track on my oc-3 would come half way off to the inside on the front roller once in a while and do the same thing.a pin coming out would be a good guess to.