How much tongue weight should a trailer have?

Tongue weight should be 10–15% of loaded trailer weight (15–25% pin weight for a fifth wheel). How to measure it, and what too little or too much does.

Updated September 12, 2026

What tongue weight is

Tongue weight is the downward force a loaded trailer puts on the hitch ball — the share of the trailer’s total weight that presses straight down instead of riding on the trailer’s own axles. On a fifth wheel or gooseneck the same idea goes by a different name, pin weight, for the downward force on the truck bed’s hitch point. Either way, it’s weight the trailer carries but the truck feels, and it’s the number that decides whether a trailer tows straight or hunts side to side at highway speed.

It isn’t a fixed property of the trailer itself — it’s a function of how the trailer is loaded. Two identical trailers carrying the same total weight can have very different tongue weights depending on where that weight sits relative to the axles. Cargo loaded ahead of the axles adds to tongue weight; cargo loaded behind them subtracts from it. That’s what makes tongue weight something you check and adjust for a given trip, not a number that’s baked in once and forgotten.

The right range

For a bumper-pull trailer, tongue weight should land between 10–15% of the trailer’s total loaded weight. For a fifth wheel or gooseneck, where more of the trailer sits over the truck, the range runs higher: 15–25% pin weight. Those aren’t rules of thumb pulled from a forum — they’re the ranges hitch makers publish. The app checks the same 10–15% / 15–25% range — computed against the trailer’s GVWR — the calculator does this when you’ve entered one, the app always does — so its figure can read a little lower than the true loaded-weight percentage.

Too little: sway

Under the range, a trailer is rear-heavy relative to its hitch point, and a rear-heavy trailer is unstable at speed. Enough of the trailer’s weight sits behind the axles that a crosswind, a passing semi’s wake, or a quick steering correction can start the trailer oscillating side to side — and once it starts, the trailer’s own momentum keeps feeding the oscillation. That’s the classic dashcam-video scenario: a trailer that looked fine pulling out of the driveway starts fishtailing a few miles down the highway, and by the time the driver feels it, the swing is already building.

Too much: an overloaded truck

Over the range causes a different problem. Tongue weight doesn’t ride on the trailer’s axles — it presses down on the truck’s hitch, which means it comes straight out of the truck’s payload the same as a passenger or a cooler in the bed. Too much of it squats the rear of the truck, lightens the front tires’ grip on the road for steering, and lengthens braking distance. It’s also usually a payload problem wearing a tongue-weight disguise: heavy tongue weight is one of the fastest ways to eat a truck’s payload budget without anyone loading a single thing into the bed. A truck that looks lightly loaded — one passenger, an empty bed — can still be over its payload rating if the trailer behind it is pushing 1,000 lb or more down on the hitch, which is why tongue weight belongs in the same math as everything else riding in the truck, not off to the side as a “towing” number.

How to measure it

A dedicated tongue-weight scale sits under the coupler and gives a direct reading before you ever hitch up — the simplest and most accurate option if you have one. For lighter trailers, a bathroom scale and a length of pipe as a lever can approximate it: rest the pipe on the scale a known distance from the coupler and do the arithmetic on the lever ratio. For anything heavier, a CAT scale works: weigh the truck alone, then weigh the truck with the trailer attached but the trailer’s own axles held off the scale, with the weight-distribution bars unhooked — the difference between the two readings is the tongue or pin weight. With the bars tensioned, the difference isn’t the tongue weight. Whichever method you use, measure it loaded the way you actually plan to travel — water tanks filled or drained, gear stowed where it’ll ride — since tongue weight moves with the load, not just with the empty trailer.

Worked example

That 7,000 lb trailer started at 500 lb of tongue weight — 7.1% — which is below the 10–15% range and a sway risk at highway speed. The fix isn’t less cargo, it’s the same cargo in a different spot: moving the heavier items forward of the trailer’s axles shifts more of the trailer’s weight onto the hitch instead of the axles. Sliding gear forward until tongue weight reaches roughly 900 lb — 12.9% — puts this trailer solidly inside the range, without changing how much it’s carrying overall.

Fifth wheels

The same 7,000 lb trailer, if it were a fifth wheel or gooseneck instead of a bumper-pull, would carry far more of its weight over the truck: 20% pin weight on a 7,000 lb trailer is 1,400 lb, and every pound of it lands on the truck’s payload, not the trailer’s axles. That’s why the fifth-wheel range runs higher than the bumper-pull range in the first place — the hitch sits over the truck’s rear axle rather than behind the rear axle, so more pin weight is normal and expected. It’s also why payload disappears faster behind a fifth wheel than behind a comparable bumper-pull: 1,400 lb of pin weight is a much bigger bite out of a typical half-ton’s payload than the 700–1,050 lb a bumper-pull trailer of the same size would put on the hitch. That’s not a flaw in fifth wheels — the hitch geometry is what makes them tow so much more stably than a bumper-pull of the same weight — but it does mean the truck’s payload rating deserves an even closer look before you buy or hitch up one of these trailers, since pin weight alone can use up most of a half-ton’s available payload before a single cooler goes in the bed.