what you need to do is measure the distance from the lip of the trailer to the ground when it is level, and the distance from the hitch hole to the ground (on the truck). The difference of these two will tell you what sort of drop you need (in my case I needed a 6" drop, i have a 4" lift on my truck!)
eta: trailers can vary at what distance from the ground they sit at level, just as trucks can vary in height.
Last edited by EventingJ; Mar. 22, 2011 at 09:33 AM.
Reason: edited for clarification
I would recommend getting the ball about 2 inches higher than level trailer tongue. You want empty trailer to ride higher than loaded trailer.
Reason is that weight of LOADED trailer will push tongue down, truck rear down, so then your trailer with horses inside, is going downhill if you started with a leveled hitch.
My trucks with a hitch have always had the ball set above level for the trailers they pulled. First trailer hitch I had put on, the installer explained this reasoning to me. My horses rode level in their trailers.
You probably don't want to call this a bumper hitch on your truck. Brings visions of those old strap on hitches, or the ball fastened in the hole of your step bumper, for pulling trailers. REALLY unsafe, certainly not up to pulling a horse trailer. The ball fastened in step bumper is also UNSAFE, because those bumpers are just fastened with white metal bolts, which break easily. You could have the rear bumper and trailer tongue on the ground really fast with either setup!!
The hitch on the truck should be called a frame hitch, fastened underneath to the frame of truck. Weight spread out for strength.
TRAILER is called a bumper pull, for the level it rides at, though bumper is not actually where you would attach it.
I've yet to see a walmart that carries anything other than the hollow 500lbs tongue/5000lbs 2" drawbars, not something I would pull a horse trailer with.
But I've not been in all walmarts..........
Mine sells the Class IV 1000lb TW/10000GTW ones. I've even seen a Class V one there from time to time. There's always just one or two though, hidden among all the Class III ones, so you have to look. -shrug-