Do you have the 5.4L V8 with 300 HP or a smaller engine?
Auto trans? 4 wheel drive? Towing package?
The towing package usually includes a larger transmission cooler, and if you want to tow above about 8,500 pounds GVWR for the trailer, then a larger transmission cooler would always be a good idea.
Like stated above, the GVWR of the truck is what can be put on those 4 tires, and try your best to not exceed the 7,200 pound rating. The tires, rims, axles, brakes, and other items like the transmission strength are all limiting factors that Ford used to decide the F-150 has a rating of 7,200 pounds.
Ford also takes a hand built 2008 truck and loads it up to 7,200 pounds and takes it all over the test tracks. They brake with it, do many full throttle tests, then full braking, and see what happens. Do the brakes overheat at 7,500 pounds? If something looks unstable, they will only allow a lower GVWR, to make sure the truck will last a full 100,000 miles without undue problems showing up. Such as overheating brakes when you are driving in city traffic and go to 35 MPH for 600 feet, then a complete stop for 20 seconds, and repeat for about a hour. If the brake pads had started to glow, then it would indicate something not "Ford Tough".
And while testing, they have all kinds of gauges on the trucks. Measure transmission temps, axle oil temps, test the brakes then measure the rotor temps, and on and on.
Basically the 1/2 ton can carry about 1,000 pounds and still have ability to carry a driver, full tank of gas, and other small items.
So basically start looking for a 6,000 pound trailer with about 600 - 750 pounds of hitch weight. You can go over a few hundred pounds, but towing might be slower up the hills, or not? Anyway in 2011, the 3.5L Ecoboost 365 HP engines came out with a 7,600 pound GVWR (give or take a few hundred pounds) and it can tow 10,500 pound trailers. They did not declare that you could actually carry 6 passengers while towing that 10,500 pound trailer, but you can carry about 500 pounds of passengers and still tow the trailer.
Fred.
Money can't buy happiness but somehow it's more comfortable to cry in a
Porsche or Country Coach!
If there's a WILL, I want to be in it!
I havn't been everywhere, but it's on my list.
Kangen.com Alkaline waterEscapees.com