I run a grade 70 3/8 chain through the tube that goes through the FEL arms,hooked on one side to the stake pocket with the rest of the chain looped back through the stake pocket on the other side and pulled tight with a ratchet chain binder. This does 2 things, pulls the tractor down and the grapple against the front edge of the trailer frame. The tractor cannot go forward or backward or get off the floor of the trailer,I also do the same with a chain using the rear stake pockets,as I always have a piece of equipment on the rear,bush hog,tandem disc's, blade, etc, I chain over,around through so that tractor cannot move in any direction. Trailer is 18 ft dovetail equipment trailer w 3500 lb axles w brakes on both axles. You get a pole long enough to push the hook on the chain through the tube on the FEL. I use a flagpole from a golf course that "fell" into my mom's 66 Ford Country Sedan station wagon in the 70s. Just be safe and chain/ strap so that if anything unexpected happens , your tractor stays on the trailer. Good luck to all on your projects.
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