A trailer should ride level behind your truck. When the nose points up or down, weight lands in the wrong place, tires wear unevenly and braking gets worse. The ball mount sets that height, so it is worth getting right.
The three parts of a ball mount
- Shank: the square bar that slides into your receiver. Most pickups use a 2" receiver. Some heavy-duty hitches use 2-1/2" or 3".
- Drop or rise: how far the ball platform sits below the shank (drop) or above it (rise).
- Ball: it has to match the coupler on your trailer.
Step 1: Measure the drop you need
- Park the truck and trailer on level ground. Load the truck the way you normally tow.
- Level the trailer with its tongue jack. Measure from the ground to the bottom of the coupler.
- Measure from the ground to the top of the inside of your receiver opening.
- Subtract the coupler height from the receiver height. That number is the drop you need. If the coupler sits higher than the receiver, you need rise instead.
Example: the receiver is 21 inches off the ground and the coupler is 17 inches off the ground, so you need about a 4 inch drop. Lifted trucks often need 6 inches or more.
Step 2: Match the ball size
The ball size is stamped on the trailer coupler. These are the common sizes:
| Ball size | Typical trailers |
|---|---|
| 1-7/8" | Light utility trailers and small boats |
| 2" | Most boat, utility and camping trailers |
| 2-5/16" | Heavier equipment trailers, car haulers and larger campers |
Step 3: Check every weight rating
- Gross trailer weight (GTW): the most the loaded trailer can weigh.
- Tongue weight (TW): the downward push on the ball. Plan on about 10 to 15 percent of the loaded trailer weight.
- The lowest rating wins. The truck, receiver hitch, ball mount, ball and coupler each have a rating. Your setup is only as strong as the lowest one, and you should never go over your truck's towing rating in the owner's manual.
Fixed or adjustable?
Fixed ball mounts are one piece with one drop. They cost the least and work well if you only tow one trailer.
Adjustable ball mounts let you change the height, so one mount handles the boat, the camper and the utility trailer. The B&W Tow & Stow is a good example. It adjusts in 1 inch steps, many versions carry two or three ball sizes on one mount, and it flips up under the bumper when you are not towing, so you stop banging your shins on it. The popular 2" Model 6 dual-ball version is rated for 10,000 lb gross trailer weight and 1,000 lb tongue weight.
For heavier or rougher towing, GEN-Y hitches use a torsion system that soaks up bumps between the truck and trailer. Their BOSS Torsion-Flex drop hitches start at a 10,000 lb rating.
Towing a big camper?
A weight distribution hitch spreads tongue weight across the truck and trailer axles, which keeps the front of the truck planted. For fifth wheels and goosenecks, see our fifth wheel hitches and gooseneck hitches.
Quick checklist before every trip
- Hitch pin and clip are in and locked.
- Ball nut is tight to the ball maker's spec.
- Safety chains are crossed under the tongue.
- Trailer lights and brakes work.
- The trailer sits level once it is hooked up.
Shop hitches and ball mounts
Browse adjustable hitches and ball mounts, all B&W trailer hitches and towing accessories. Not sure what drop you need? Send us your receiver and coupler measurements and we will help you pick. Call Truck Covers MN at (218) 308-0045, Monday to Friday, 7:30 to 5, or stop by our shop at 3002 Bemidji Ave N in Bemidji, MN.