My grandpa's 500 ho is stuck in reverse. Any suggestions? It is below freezing here.

 

remove the side panel next to shifter. next take the nut off eack of the linkage arms at the shifter end wiggle everything around and it will very easily unbind.put it back together...take about 3 mins in total. mines done it twice in a year....i have an extra wrench in the tool kit to do the job. both times it was -20 c at least....