Originally Posted by nothermark
It sounds like somebody needs to get or print a copy of the towing guide and sit down with Dad and figure out the actual loads involved.
The towing guide won't help. It will only confirm what Dad thinks he knows. The towing guide includes the truck manufacturer's "tow rating" of the tow vehicle, but ignores the payload capability of the tow vehicle.
For example, the towing guide for my pickup says the tow rating is 8,400 pounds max trailer weight. But my pickup is overloaded over the GVWR of the pickup with my TT that grosses only 4,870 pounds. My previous pickup had a fifth-wheel tow rating of 13,000 pounds, but it was overloaded over the GVWR of the pickup with my 5er that grossed only 8,000 pounds.
The towing guide includes the word "maximum", but very few people consider what that word means. It means that provided
there is nothing in the truck but a skinny driver so without the trailer it weighs no more than (GCWR minus tow rating), and the hitch weight is the minimum safe percentage of trailer weight (10% for TTs and 15% for 5ers), then the truck can tow a trailer that weighs up to the weight of the tow rating without being overloaded. But it's a very rare rig that can meet those conditions. TTs average about 12.5% tongue weight, not 10%. 5ers average 17.5%, not 15 percent. And any pickup wet and loaded for a towing will weigh a lot more than (GCWR - tow rating).
So you shouldn't recommend newbees rely on the towing guide unless you also caution them to read the fine print which states: "Never exceed the GVWR or GAWRs of the tow vehicle.)