How to Select the Right Hitch Ball for Level Towing
The ball mount raises or lowers the hitch ball to ensure that your tow vehicle and trailer remain level as you travel. Correct ball mounts will match shaft size to receiver tube dimensions. The key is to get a ball mount that allows the trailer coupler to be level with the ground.
Shop Truck and Towing Parts
How to Level Your Trailer
Arrange Your Vehicle and Trailer
Park your vehicle and trailer on level ground.
Level Out the Trailer Tongue
Place a level on top of the trailer tongue, and adjust the trailer up or down until the bubble inside the level shows that the trailer tongue is level with the ground below.
Measure the Draw Bar Shank's Height
Using a tape measure or something similar, measure from the top of the part of the draw bar that connects with the receiver tube to the ground. Record this measurement and label it A.
Measure the Trailer Tongue's Height
Get your tape measure again and measure from the bottom of the trailer tongue to the ground. Record this measurement and label it B.
Subtract for Drop
Subtract B from A for the amount of "drop" you will need to keep your trailer level (A - B = "drop").
If the "drop" value is negative, it is referred to as "rise."
What is a Ball Mount?
A Ball Mount is a removable hitch ball platform that slides into the receiver of a hitch and fastens with a pin and clip. Different ball mounts can be used to raise or lower the height of the ball to allow for level trailer towing.
Different classes of ball mounts fit different receiver tubes:
- Class I & II: 1-1/4″ receiver tube
- Class III & IV: 2″ receiver tube
- Class V: 2″ or 2-1/2″ receiver tube
It is important to identify mounting location, hitch ball, shank diameter, and thickness if you are not purchasing a combo. Then you can measure the diameter of the hole and thickness of the mounting location to choose a matching ball mount.
What is a Hitch Ball?
A hitch ball (or trailer ball or just ball) is the ball-shaped attachment that connects the trailer to a hitch. While the diameter of the hitch ball is fairly standard, shank diameters, and hitch ball weight ratings may differ. The rating of the hitch ball is just as important as the receiver hitch ratings.
Ball Diameter (A): Check the top of the trailer coupler for the size of the ball diameter required. The size is usually stamped there. Recreational and light commercial hitch balls come in a variety of sizes including 1-7/8″, 2″, 2-5/16″ and occasionaly 3″. In general lighter trailers use smaller hitch balls. It is VERY important to match the trailer to the correct hitch ball.
Shank Diameter (B): This is the diameter of the threaded shaft that is inserted through the ball mount. Shanks come in a variety of sizes (5/8″, 3/4″, 1″, and 1-1/4″) and capacities. (7,000lbs-17,000lbs)
Shank Length (C): This is length of shaft that extends beyond the mounting base of the hitch ball. It is important to use a shank that is long enough to extend beyond the thickness of the draw bar mounting tab to ensure that enough threads are available to securely fasten the ball to the mount.
Shank Rise (D): The height of the shank can be used to raise a trailer back to level in the event the “rise” or “drop” of a ball mount is inadequate.
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