Tongue Weight: How Much, Why It Matters, and How to Measure It

Tongue weight is how hard the trailer presses down on your hitch. Get it right and the trailer tracks straight. Get it wrong and you get sway or an overloaded rear axle.

How much is right

• Bumper-pull trailers (receiver hitch): 10 to 15% of the loaded trailer weight.
• Fifth wheels and goosenecks: 15 to 25%, often called pin weight.
• Boat trailers: often lighter, around 5 to 10%. Check the boat or trailer maker's guidance.

A 5,000 lb travel trailer should put about 500 to 750 lbs on the hitch.

Too little or too much

Too little (under about 10%) is the classic cause of trailer sway, especially at highway speed or when a semi passes. Too much overloads the rear axle, lifts the front of the vehicle, and takes weight off the front tires, which hurts steering and braking.

Tongue weight counts against your payload. That's why it matters even when the trailer is under your towing rating. See towing capacity vs. payload.

How to measure it

1. Tongue weight scale. A purpose-built scale you set under the coupler. The easiest option.
2. Truck stop scale. Weigh the vehicle alone, then hitched to the trailer with the trailer's wheels off the scale. The difference on the vehicle is roughly the tongue weight.
3. Bathroom scale. Works for small trailers with light tongues. For heavier ones, people use a beam-and-block lever setup, but a real scale is more reliable.

Fixing it

Move heavy gear forward of the trailer axle to add tongue weight, or back to reduce it. Many owner's manuals require a weight-distributing hitch above a certain trailer weight, and many people add sway control for larger campers. Check what yours says.