As noted in the post above, the manufacturers arrive at the tow rating by considering engine power, engine cooling capacity, transmission capacity and cooling, suspension capacity, axles, springs, tires, frame strength, hitch rating, brakes, although all manufacturers require brakes on the trailer/toad above a minimal weight, ability to control the rig, etc. Sometimes these ratings are optimistic and sometimes conservative, but the manufacturers tow rating should be followed.
Hitches can be beefed up, but that's just a band aid.
Adios, Dirk - '84 Real Lite Truck Camper, '86 Wilderness Cimarron TT, previously 4 years as a fulltimer in a '07 DSDP
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