Measure from the top of the ball to the flat part of the base where the ball will sit on the hitch head. Do not include the length of the threaded shank.

Measure from the ground directly below the receiver to the inside top of the receiver tube (where the top of the shank will be).

Level the trailer. Measure to the frame on the front & back of the trailer and use the tongue jack to raise or lower it until the measurements at both ends are the same, and the trailer is sitting parallel to the ground.

Measure from the ground to the top of the socket where the hitch ball fits into the coupler.

Newer heavy duty trucks sometimes come equipped with a 2-1/2” or even a 3” receiver. Equal-i-zer hitches will not fit receivers smaller than 2”. They can be used with 3” receivers by using a 2-1/2” shank, and the correct adaptor sleeve if allowed by the vehicle manufacturer.

An extended shank length gives you more room behind the tow vehicle to give more clearance for things like a tail-gate mounted spare tire. Most configurations do not need an extended length, and using the shortest shank possible is the safest option.

The 4K model uses a lighter-weight shank than the 6K-14K models. They are not interchangeable. Choose this option only if you have or are purchasing a 4K Equal-i-zer hitch. Use the hitch size calculator to determine the Equal-i-zer hitch model you need.