Sounds like he's trying to remove the gland cap of the bucket roll cylinder, the loader arm cylinders on the 953 don't use the bolt on gland. The gland is probably just stuck from rust on the inside of the bore of the cylinder on the outside of the inner o-ring seal. I've done the same thing 2stickbill describes. I've pulled the pin that attaches the cylinder rod to the bucket roll link, lift rod out of roll link and support it, loosen the four gland bolts just a few threads, then use the machines hydraulics to extend the rod until it bottoms out on the gland and put some hyd pressure on it to force the gland out until it catches up with bolt heads. Loosen bolts a couple more threads and do it again. Just don't push the gland so far out with pressure that the o-ring is exposed, you'll make a big mess then.