TrailerTowCalc

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How to Choose a Trailer the Truck Can Tow

Built by Jeremy Panasuk · Published October 3, 2026

The category tells you the shape. The loaded weight tells you whether the hitch column, and then the truck, can take it.

Quick answer: NHTSA groups trailers into four categories and says to use fully loaded weight, weighed at a public scale, not the dry weight. At Ford's 10 percent tongue-load note, this site's function puts 500 lb on a 5,000 lb trailer and 1,080 lb on a 10,800 lb trailer. Five hundred pounds fits CURT Class 3 weight-carrying. One thousand eighty pounds does not. It sits under the 1,200 lb weight-distribution tongue rating.

The four categories, and what they do not decide

NHTSA says there are numerous types of trailers and that, in general, they fall into four categories: flat bed or open trailers, boat trailers, enclosed trailers, and recreational vehicle trailers. The last group includes travel trailers, fifth-wheel trailers, and folding camping trailers. The same paragraph says the tow vehicle and the equipment depend on the type, the size and weight, and the amount of weight being towed. The category is a starting label. It is not a rating.

If you already have the truck, NHTSA says to look up the tow rating in the owner's manual: size, maximum loaded weight, and maximum tongue weight. Manufacturers' ratings cover the gross vehicle weight rating (how much the tow vehicle may weigh fully loaded), the weight the vehicle can tow (which may change with transmission and four-wheel drive), the gross combination weight rating, and the gross axle weight rating. A matching hitch has to handle the same specifications. A towing package, when a manufacturer offers one, may include a heavy-duty radiator, battery, flasher, alternator, suspension, and brakes, plus an engine-oil cooler, a transmission-oil cooler, a wiring harness, a specific axle ratio, and special wheels and tires. It may include the receiver. It rarely includes the draw bar and the ball.

Dry weight is the wrong shopping number. NHTSA's example is an open trailer carrying a boat or motorcycle: fully loaded weight includes the trailer, the boat or motorcycle, and additional items such as fuel tanks, motors, and safety equipment. The practical way to get the actual weight is a public scale. Too little tongue weight can cause sway. Too much can take weight off the front wheels so the tow vehicle is less responsive to steering. A weight-distributing hitch can transfer weight to the front axle. The GAWR on the certification label must not be exceeded.

Two loaded weights, one tongue function

Both examples use 10 percent because that is the tongue-load percentage in the 2025 F-150 conventional towing notes: tongue load should be 10 percent of total loaded trailer weight. CURT says tongue weight should be about 10 to 15 percent of gross trailer weight, so 10 percent is the bottom of CURT's band and the figure Ford prints, not a second rule.

The first trailer weight is 5,000 lb. That is the weight the F-150 guide says not to exceed when towing without a weight-distribution system, and it is the weight-carrying trailer capacity on the F-150 factory hitch-receiver chart, which pairs it with a 500 lb tongue. Ford says those receiver capacities may exceed the vehicle's maximum loaded trailer weight, so the chart is a hitch limit, not a permission slip.

Inputs to TTC.tongueWeight: trailer 5,000 lb, measured percentage 10.

OutputValue
Tongue weight500 lb
Percent10%
Targets the function prints (10 / 12 / 15%)500 / 600 / 750 lb
VerdictIn the safe 10–15% band

CURT Class 3 weight-carrying is up to 8,000 lb gross and 800 lb of tongue. Both 5,000 and 500 fit that column. The 12 percent target (600 lb) is this calculator's midpoint of CURT's band. Ford's note does not ask for 12 percent.

The second trailer weight is 10,800 lb. On the 2025 F-150 Hybrid selector, a 3.5L Hybrid V6 with a 3.73 axle and a GCWR of 17,100 lb lists a conventional maximum loaded trailer weight of 10,800 lb for both the SuperCrew 4x4 145.4-inch wheelbase and the 157.2-inch wheelbase. The 18,400 lb GCWR row above it is a different line and carries a footnote requiring the Tow/Haul package and the Max Tow axle. Do not borrow the 10,800 lb figure from a truck that is not that row. The engine-summary maximum payload of 1,815 lb for the PowerBoost is a different part of the same guide. Ford says horsepower, torque, payload, and towing may not be achieved simultaneously, so this page does not add 1,815 lb onto the 17,100 lb row and call it one truck.

Inputs to TTC.tongueWeight: trailer 10,800 lb, measured percentage 10.

OutputValue
Tongue weight1,080 lb
Percent10%
Targets the function prints (10 / 12 / 15%)1,080 / 1,296 / 1,620 lb
VerdictIn the safe 10–15% band

The verdict is about the 10–15 percent band. It is not a hitch-class pass. One thousand eighty pounds is over the Class 3 weight-carrying tongue cap of 800 lb and under the Class 3 and Class 4 weight-distribution tongue rating of 1,200 lb. The hitch column changes between these two trailers before anyone opens the payload tab. Combined weight still cannot exceed the listed GCWR, and tongue plus passengers and cargo cannot exceed rear GAWR or GVWR on the Safety Compliance Certification Label. Ford says the selector ratings were calculated with SAE J2807. The four limits, and why the smallest one wins, are in towing capacity explained. Enter the sticker you actually have in the calculator.

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Tongue weight scales

A common mistake

Shopping the dry weight, or shopping the biggest "max tow" number on the engine page, and buying the trailer before the tongue weight has a hitch column. The 10,800 lb example is inside CURT's percentage band at 10 percent and still over a Class 3 weight-carrying tongue. The other miss is assuming a larger receiver raises the truck. CURT's adjustable-hitch guide says an adjustable hitch does not itself alter the vehicle's towing capacity. You still have to choose one that matches the vehicle's rated capability, and you still must not exceed any component.

Limits, and when to stop shopping

This page does not pick a floorplan. It compares two published weights to one hitch chart and one function. If you cannot find GVWR, tow rating, GCWR, and GAWR for the exact truck, NHTSA's instruction is to look them up before you match a hitch. A public scale is how you replace a brochure dry weight. Fifth-wheel and gooseneck selection is a bed-mounted hitch, not a receiver class: fifth-wheel hitches. The first time you leave with a new travel trailer is a checklist problem as well as a math problem: towing a new travel trailer.

Related

FAQ

What four categories does NHTSA use?

Flat bed or open, boat, enclosed, and recreational vehicle trailers (travel trailers, fifth-wheels, and folding camping trailers). Loaded weight still decides the tow vehicle and the hitch.

Why does 10,800 lb fail Class 3 weight-carrying if the percentage is fine?

Because 10 percent of 10,800 lb is 1,080 lb, and Class 3 weight-carrying tongue stops at 800 lb. The weight-distribution tongue rating of 1,200 lb is the column that still covers 1,080 lb. The percentage verdict and the hitch cap are different tests.

Will a bigger hitch fix a truck that is over its rating?

No. Match the hitch to the vehicle ratings NHTSA tells you to look up. An adjustable mount changes ball height. It does not change GVWR, GCWR, or the tow rating.

Compiled with AI assistance from the sources below. Spot an error? Email jpanasuk@gmail.com.

Sources