Whew, when it rains, it pours! Thanks for all of the quick responses. I was at the dealer yesterday, and I took a quick look at the 2410 and the 2910 models with folding ROPS. The 2410 has one that is wider at the top (sorta shaped like a fat light bulb). That one was very tight in both front to back and side to side directions. I am assuming that since the 7500 and 2410 are the same frames, that the ROPS are also the same. The 2910 (and also 2710) ROPS is the same width all the way up, and it had the same rattle as mine does (front to back, not in the hinge). I didn't get my tractor from this dealer, but the sales guy told me that most of them have the rattle. He also said that they tried tightening the hinge, which stopped ALL the rattles (from both directions), but makes the bar too hard to fold over. His suggestion was to live with it. I haven't tried to tighten the hinge bolt, because it wasn't the source of the rattle. I can't see how tightening there will stop the rattle I have in any way. I think this particular saleman says whatever he thinks will get you on your way and out of his hair.
Craig, if your 7500 is shaped like the one I saw on a 2410, and it rattles that way, then some (yours, anyway) do and some (the dealers demo) don't. This then is probably also true of the other models. The question is, what is different between these tractors. My bar does indeed fit over the lower bar structure. I thought about shims, too. In fact, I thought maybe a shim/gasket was left off during assembly. I thought that a rubber boot between the top and bottom pieces would work best. Can anyone verify whether your ROPS has a rubber shim/gasket/boot between the top and bottom pieces where they bolt together (just above the fender)?
A missing gasket would be easier to believe than such loose tolerances. It just seems that so much of the engineering on this tractor is so good, that they WOULDN'T have made it so loose without some reason, would they??? I just wonder what those reasons might be....
PaulT