Weight Distribution
To select the right hitch and tow vehicle the total weight of the trailer and its contents must be known. This is the Gross Trailer Weight (GTW). It includes the trailer itself and everything that will be on or in the trailer when towed. The maximum GTW is on the trailer specification label. If not, check with the trailer manufacturer. To accurately determine the GTW, the loaded trailer must be placed on a vehicle scale.
The Tongue Weight (TW) is the weight that will rest on the trailer ball and receiver hitch. As the trailer load is shifted ahead or behind the trailer axle(s) the tounge weight will change. The trailer should be loaded so the Tongue Weight is approximately 10-15 percent of the GTW.
When trailer and tow vehicle are connected they should be level. This is acheived by using correct ball height, correct tongue weight and a properly weighted trailer. For heavy trailers a weight distribution hitch may be required.
A weight distribution hitch uses special bars on the hitch to distribute weight forward on the tow vehicle. The bars are pulled up to the trailer tongue with chains and a removable lever. They are pinned in place.