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How Ball Mounts Work

Choosing Ball Mounts
A trailer hitch
Dan Driedger/iStockphoto
It's important to select the appropriate ball mount for your specific towing needs.

Several important factors come into play when determining which ball mount is right for you. These include vehicle type, towing capacity, and of course, trailer and load size. Trailer hitches, ball mounts and couplers are classified by the amount of weight they can withstand safely.

The two measurements towing accessories are typically measured by are gross towing weight (GTW) or overall weight of the trailer and load, and tongue weight (TW) which is the weight of the trailer tongue at the point where the ball mount and trailer hitch meet. In some cases, when weight distributing spring bars and other towing accessories are installed on the towing vehicle, the GTW and TW can be increased. Before we learn about your ball mount options, let's take a brief look at class ratings and the weight range each covers.

Hitch Class Max TW (WC) Max GTW (WC) Max TW (WD) Max GTW (WD)
I up to 200 lbs. up to 2,000 lbs. N/A N/A
II up to 300 lbs. up to 3,500 lbs. N/A N/A
III up to 600 lbs. up to 6,000 lbs. up to 1,000 lbs. up to 10,000 lbs.
IV up to 1,000 lbs. up to 10,000 lbs. up to 1,400 lbs. up to 14,000 lbs.
V up to 1,200 lbs. up to 12,000 lbs. up to 1,700 lbs. up to 17,000 lbs.


Now that you understand this classification system, you'll want to keep it in mind when you choose a ball mount because you'll see that information again. Ball mounts came in three common styles; straight cut, angle cut and drop cut. All three types are listed by their GTW and TW. When choosing the appropriate ball mount, you first must consider the trailer's maximum GTW and TW and compare that to the towing capacity of your vehicle. For example, if your vehicle has a 6,000-pound towing capacity, it makes no sense to choose a ball mount with a class IV or V rating. Let's take a look at the most common ball mounts you'll see for use on light passenger or heavy duty pickup trucks:

  • ¬≠Self aligning -- ball mount with integrated aligning system similar to forming a "V" to guide the trailer coupler on to the ball
  • Multi-ball -- mount that has a ball on three or four sides that can be rotated to accept different sized couplers
  • Cushioned ball mounts -- mounts that act as a shock absorber so that the trailer weight doesn't damage the drivetrain during acceleration and braking
  • Integral ball -- a one-piece mount that does not have an opening to accept different balls; the ball is part of the mount
  • Dual-ball mount -- similar to multi-ball mounts, yet only has two balls
  • Triple-ball with pintle hook -- similar to multi-ball mounts only these integrate a pintle hook as well for use with lunette ring trailer couplers

Okay, so you've determined the weight of your trailer and the load you plan to tow. Now it's time to check the height of your hitch. Remember the trailer we talked about earlier that sloped at that funny angle? You don't want to make that mistake when you choose your ball mount. The height of your trailer could be the difference between safe towing and an accident. In order to avoid an uneven trailer load, we have to measure the trailer and hitch to make sure the vehicle and trailer are level. Remember, we want the trailer and vehicle to work as one.

First, with the towing vehicle on level ground, measure the height of your hitch receiver from the ground to the top of the ball mount opening. Next, measure the height of the hitch coupler on the trailer. Make sure the trailer is level. If the difference is greater than zero, you need a drop mount. If the difference is less than zero, you need a rise mount. In either case, mounts are available with the right amount of rise or drop to compensate for the trailer or vehicle.

Let's take a look at what you might expect to pay for a ball mount, and also determine how to install various mounts, in next section. You might be surprised at how easy it can be.