Choosing the Correct Ball Mount

For safe and comfortable towing, the trailer should always be as level as possible. A level trailer will put less strain on the connection between the trailer and hitch. It will also help the trailer stay in line behind the vehicle. Because trailer and vehicle heights often differ, a ball mount with a Rise or a Drop may be needed. To determine how much of a rise or drop you need, follow the simple steps below.

Measuring for Your Ball Mount

Measure the hitch height - from the ground to the top of the receiver opening on the trailer hitch. With the vehicle parked on level ground, measure to the top of the 2" hole on class III and IV hitches, and 2-1/2" hole on class V hitches.

Measure the Coupler Height - from the ground to the bottom of the trailer's coupler. Make sure the trailer is level, and on level ground.

Compute the difference between the hitch height and the coupler height. If the hitch height is greater than the coupler height, the difference is the drop that is required. If the coupler height is greater, the difference is the rise that is required. The ballmount with the rise or drop closest to the difference should then be chosen. For example, if the hitch height equals 24-3/4" and the coupler height equals 17". Because the hitch height is greater, a ballmount with a drop of 7-3/4" would be required for a level trailer. The ballmount with an 8" drop is the closest one offered and would therefore be chosen.

If the hitch height is greater than the trailer height then

• hitch height - trailer height = drop

If the trailer height is greater than the hitch height then

• trailer height - hitch height = rise

Ball Mount Dimensions

Drop: Is the distance from the top of the shank to the top of the ball platform.

Rise Is the distance from the top of the shank to the top of the ball platform.

Length: Is the distance from the center of the ball hole to the center of the pin hole. The length will determine how much clearance will be available between the vehicle and the trailer, and can be used to get past a spare tire or tailgate.

Ball Hole Diameter: Is the size of the hole in the platform of the ball mount. This measurement will determine what diameter shank your hitch ball should have to properly fit in the ball mount. Typical sizes are 3/4", 1" and 1-1/4".

Ball Mount Classes

Class I Ball Mounts

When towing with a class I trailer hitch, the ball mount that is recommended by the manufacturer should be used. All class I trailer hitches are tested and rated with the specific ball mount for that hitch. Using a ball mount that is not recommended by the manufacturer will void the warranty.

• Has a 1-1/4" x 1-1/4" shank
• Class II ball mounts will not fit on Class I trailer hitches
• Held in place with a 1/2" pin
• Uses ball with a 3/4" shank diameter
• Rated for 2,000 lbs GTW
• Only 1-7/8" or 2" hitch balls can be used

Class II Ball Mounts

When towing with a class II trailer hitch, the ball mount that is recommended by the manufacturer should be used. All class II trailer hitches are tested and rated with the specific ball mount for that hitch. Using a ball mount that is not recommended by the manufacturer will void the warranty.

• Has a 1-1/4" x 1-1/4" shank
• Class II ball mounts will not fit on Class I trailer hitches
• Held in place with a 1/2" pin
• Uses ball with a 3/4" shank diameter
• Rated for 3,500 lbs GTW
• Only 1-7/8" or 2" hitch balls can be used

Class III Ball Mounts

Class III hitches and ball mounts are rated to tow up to 6,000 lbs GTW Class III ball mounts will work with trailer hitches with a 2" x 2" opening. The GTW and TW of the ball mount should match or exceed the trailer hitch.

• Has a 2" x 2" shank
• Held in place with a 5/8" pin
• Uses ball with a 1" or 1-1/4" shank diameter
• Rated for up to 6,000 lbs GTW
• Can use a 1-7/8", 2", or 2-5/16" hitch ball
• Weight distribution system can allow for more weight to be towed

Class IV Ball Mounts

Class IV hitches and ball mounts are rated to tow up to 12,000 lbs GTW Class IV ball mounts will work with trailer hitches that have a 2" x 2" opening. The GTW and TW of the ball mount should match or exceed the trailer hitch.

• Has a 2" x 2" shank
• Held in place with a 5/8" pin
• Uses ball with a 1-1/4" shank diameter
• Rated for up to 12,000 lbs GTW
• Can use a 1-7/8", 2", or 2-5/16" hitch ball
• Weight distribution system can allow for more weight to be towed

Class V Ball Mounts

Class V hitches and ball mounts are typically rated to tow 12,000 GTW. Class V ball mounts will work with trailer hitches with a 2-1/2" x 2-1/2" opening. When towing with class V receiver hitches, the GTW and TW of the ballmount should match or exceed the receiver hitch.

• Has a 2-1/2" x 2-1/2" shank
• Held in place with a 5/8" pin
• Use a ball with a 1-1/4" shank diameter
• Rated for up to 14,000 lbs GTW
• Can use a 1-7/8", 2", or 2-5/16" ball
• Weight distribution system can allow for more weight to be towed

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