How to Find Towing Capacity: How the Lowest-of-Three Rule Works
How to Find Towing Capacity is a lookup task, and the reliable sources are the owner's manual, the door-jamb sticker and the VIN plate — not a forum post or a single number quoted for a whole model range. This page explains where each rating lives, how to decode the VIN plate, and how to combine the three ratings into the one number that actually limits what you can tow.
Never exceed your vehicle's GVWR, GCWR or payload. Check the owner's manual and the door-jamb sticker for the ratings that apply to your exact vehicle, and treat every figure on this page as a worked example unless it comes from your own vehicle's plates.
The method: the lowest of three ratings for how to find towing capacity
Three ratings decide what you may tow, and the answer is the smallest of them: the vehicle's tow rating, the tow-bar rating and the trailer's ATM — the aggregate trailer mass, the most the loaded trailer is rated to weigh. Here the worked example uses 9,000 lbs for the vehicle, 5,000 lbs for the tow bar and 8,000 lbs for the trailer ATM, which makes the towing capacity 5,000 lbs. Those numbers are examples, not ratings for any real vehicle: read the three figures off your own manual and plates and the same step gives your answer. Each rating guards a different part of the rig — the vehicle's engine, transmission, brakes and cooling; the tow bar and its mounting; the trailer's axles, tyres and brakes — so the weakest link sets the limit.
There is a second layer of limits behind the tow rating. The loaded vehicle may not exceed its GVWR, the vehicle-plus-trailer combination may not exceed its GCWR, and the payload — the gap between kerb weight and GVWR — has to cover passengers, cargo and the tongue weight of the trailer. That last point is the one people miss: the hitch load is carried by the vehicle, so a heavy trailer shrinks the payload left for everything else. Pass the tow-rating check and still fail GCWR or payload, and the combination is overloaded. Check all three against the figures for your exact vehicle in the manual and on the door-jamb sticker.
how to find towing capacity: Where to find your ratings
Four plates and documents carry the whole answer. The owner's manual lists tow ratings by engine, axle ratio and configuration and states GVWR and GCWR. The driver's door-jamb sticker gives the GVWR and payload for your exact vehicle as built. The tow-bar rating plate sits on the bar or by the receiver. The trailer's compliance plate shows its ATM and tare weight. Read all four, and if two sources disagree, use the lower figure and ask a dealer to confirm for your VIN. Ratings shift with engine, axle ratio, cab, bed length and tow package, so a figure for a different configuration — or one copied from a forum — is not a substitute.
how to find towing capacity: Worked example: the three ratings and the payload check
Take a 6,000 lbs loaded trailer as the example. The vehicle's tow rating is 9,000 lbs, the tow-bar rating is 5,000 lbs and the trailer ATM is 8,000 lbs. The towing capacity is the lowest of the three: 5,000 lbs. The trailer's tongue weight at 10 to 15 percent is 600 to 900 lbs, and the middle of that range — about 750 lbs — is a good target. With an example payload of 1,600 lbs, the tongue weight leaves 850 lbs for passengers and cargo. If the passengers and luggage weigh more than that, the combination is overloaded even though the trailer is inside the tow rating, and something has to come off — either the trailer load or the vehicle load. That is the whole check in one paragraph: lowest of three, then tongue weight, then payload, then GCWR. Do it with your own numbers before every trip, because the answer changes every time the load changes.
Tongue weight table for how to find towing capacity
For how to find towing capacity, the point is this: Use the table to read off the tongue-weight range for your loaded trailer weight. The middle column, 12.5 percent, is a handy loading target. Every figure is worked out from the trailer weight, so weigh the loaded trailer rather than guessing it.
| Loaded trailer weight (lbs) | 10% tongue weight | 12.5% tongue weight | 15% tongue weight |
|---|---|---|---|
| 3,500 | 350 | 438 | 525 |
| 5,000 | 500 | 625 | 750 |
| 6,000 | 600 | 750 | 900 |
| 7,000 | 700 | 875 | 1,050 |
| 10,000 | 1,000 | 1,250 | 1,500 |
how to find towing capacity: The four checks, in order
| Check | What to compare | Passes when |
|---|---|---|
| Tow rating | Trailer weight against the lowest of the three ratings | Trailer is at or below the lowest rating |
| Tongue weight | Tongue weight vs 10–15% of trailer weight | Inside the range |
| Payload | Tongue weight + passengers + cargo vs payload | Total is at or below payload |
| GCWR | Vehicle + trailer loaded weights vs GCWR | Combined weight is at or below GCWR |
Common mistakes for how to find towing capacity
- Trusting a figure quoted for a different year, engine or configuration. Tow ratings change with engine, axle ratio, cab and tow package, so only the numbers for your exact vehicle count. That is the point this page works through for how to find towing capacity.
- On this page, how to find towing capacity is the case in point: Forgetting that tongue weight counts against payload. The hitch load is carried by the tow vehicle, so it reduces the passengers and cargo you can carry by exactly that amount.
- Guessing the trailer's weight instead of weighing it. Bathroom scales and guesswork are not a substitute for a weighbridge or a proper scale, and an overloaded trailer is the most common cause of towing trouble. That is the point this page works through for how to find towing capacity.
- For how to find towing capacity, the point is this: Ignoring the GCWR. A combination can be inside the tow rating and still over the GCWR once the vehicle is fully loaded with people and luggage.
how to find towing capacity: Related calculations
For the next step, these pages apply the same method to a closely related question — or hand the arithmetic to the calculator. That is the point this page works through for how to find towing capacity.
- How Much Can a Toyota Highlander Tow
- How to Calculate Towing Capacity
- What Can I Tow With My Car
- Tongue Weight Scale Calculator
- Use the calculator
- Browse all towing pages
Putting your figure to work for how to find towing capacity
On this page, how to find towing capacity is the case in point: Use the method as a pre-trip routine. Before you hitch up, weigh the loaded trailer, confirm the three ratings from your own documents, calculate the tongue weight and check it against payload and GCWR. Note the four results and keep them with the trailer's documents. Any change in load — water, luggage, passengers, a different trailer — means a fresh check, because the numbers move with the load. Done every trip, the routine takes minutes and keeps the combination inside its limits where it matters: on the road.
Frequently asked questions
Do I need trailer brakes?
On this page, how to find towing capacity is the case in point: That depends on the trailer's weight and local rules: heavier trailers generally require their own brakes, and the threshold varies by country and by state. Check the trailer's ATM, the tow vehicle's manual and the local regulations. A trailer with brakes stops shorter and puts less load on the tow vehicle's brakes, which is why the braking requirement exists.
How much trailer can I tow?
It depends on the lowest of your vehicle's tow rating, your tow-bar rating and the trailer's ATM, capped by GVWR, GCWR and payload. In this page's worked example the lowest rating is 5,000 lbs. Substitute your own three ratings and run the same check — the answer is specific to your vehicle and your trailer, not a general figure.
What is tongue weight and why does it matter?
Tongue weight is the downward force the trailer puts on the hitch. It should be 10 to 15 percent of the trailer's loaded weight — for a 6,000 lbs trailer that is 600 to 900 lbs. Too little causes sway; too much overloads the tow vehicle's rear suspension and lightens the steering. Load the trailer to get the percentage right, then re-weigh. That is the point this page works through for how to find towing capacity.
How do I work out my towing capacity?
Take the lowest of three ratings: your vehicle's tow rating, your tow-bar rating and the trailer's ATM. Then check the tongue weight is 10 to 15 percent of the trailer weight, and check the combination against GVWR, GCWR and payload. All four checks have to pass. The ratings come from your owner's manual, the door-jamb sticker, the tow-bar plate and the trailer plate — not from a figure quoted for a different vehicle.
How do I weigh my trailer?
On this page, how to find towing capacity is the case in point: Use a weighbridge for the loaded trailer, or a tongue-weight scale for the hitch load. Weigh it loaded as it will travel — water, gas, luggage and all — because the empty weight tells you nothing about the loaded figure. Divide the tongue weight by the loaded trailer weight to check it is inside 10 to 15 percent.