Hi Andrew, thanks for that, appreciate your input.

This job just gets weirder by the day!

Fork truck was backed into a corner in the warehouse, as you'd expect, threw a sling around it to pull it forward out of the way (engine running so we could lift the forks off the floor but trans was in neutral), went to tow the truck forward and the wheels were locked solid, like you had the brakes applied, then all of a sudden theres a jerk and the wheels go free and the forklift starts to drive in forward and in reverse for a good 10-15 minutes, everything fine and then for no reason the fault happens again, jammed in reverse while in neutral.

It's coming off site so will pull valve block as you suggest and let you know what we find.