The 40' Cyclones has three 6k axles which can make for some light pin weights. Three 6k axles = 18000 lbs of braking performance plus your truck 14500 = 32550 lb of combined braking performance. This is why we see so many one ton DRW trucks pulling some very heavy loaded 40' GN triaxle trailers.
I would check on heartlandowners.org forum and see what other Cyclone owners report on pin and gross weights. Good luck
2011 Heartland Cyclone 3950. Advertised pin weight of somewhere around 3100-ish pounds. Actual scaled pin weight is 4,300 lbs. Trailer weight normally 16.5K.
I ran across a guy pulling a twin to my unit, with a 3/4 ton late model dodge. Don't remember the exact year. He had no idea what his trailer weighed, no idea what his pin weight was, and no idea the actual ratings of his truck. When I enlightened him to his likely pin weight, he laughed, saying it was no wonder his truck was on the bump stops when he left the dealer. First stop was a truck garage for some air bags.
Met him at a KOA in mid Ohio. He was from somewhere up in Canada, and his exact words were "it pulled it juuuust fine".
I know this is old, but that breaker looks like it was defective rather than a heartland assembly issue. Unfortunately rv's are not built by licensed electricians, or plumbers.
Defective how so? It wasn't just some cheap chinese knock-off which is what I first suspected. It was a cutler/hammer breaker, which is first rate.