Part of it's because the JD model numbers are so confusing. 5045 = 45HP, 5100 = 100HP. Who knew!

Seems to be a trend towards higher PTO HPs in the same frame size tractor, as well as the basic fact that maximum lift capabilities on the CUTs are very different than operating capacities on a skid loader. NX is a perfect example of that... 45HP and 60HP are the exact same tractor with the exact same loader capabilities. And while it's plenty stout at 60HP, if that's what sized the grapple I'd be in bad shape IMO. The tractors just don't have the rollback/breakout force to really get into trouble leveraging the light-duty grapples let alone the HD ones. Just about the only way I can see tearing one up is to take a run at something offset, and then I'd rather the grapple gave way than my tractor! That kind of mirrors the fact that a lot of people are buying the cheap, light grapples like the Titan and there's no "I destroyed my grapple" threads