Can your truck really tow that fifth wheel?

Dealers quote tow ratings. Trucks fail on payload. More often than not, the pin weight of a loaded fifth wheel uses up a truck's payload long before the trailer reaches its tow rating. This calculator checks the numbers that actually decide it — from your door sticker, not a marketing chart.

1 · Your truck — from the door sticker

Where to look: open the driver's door. The white-and-yellow Tire and Loading label says "The combined weight of occupants and cargo should never exceed XXXX lb." That number is your real payload — it's printed per-VIN for your exact truck, options and all. Year/make/model charts can be off by 1,000+ lb.

Payload (required) "occupants and cargo" number, in lb GVWR same door jamb, certification label GCWR owner's manual or manufacturer tow guide Fifth-wheel / gooseneck tow rating owner's manual or tow guide, for your config

2 · The trailer

How do you want to enter trailer weight? GVWR assumes the trailer loaded to its limit — how it should be checked. Dry weight is how people get in trouble. Trailer GVWR on the trailer's own VIN sticker / brochure

Pin weight percentage 22%

Most loaded fifth wheels carry 20–25% of total weight on the pin. The brochure "hitch weight" is the dry pin — loaded is always higher.

3 · What rides in the truck

Fifth-wheel hitch weight the hitch in your bed counts against payload People (and pets) in the cab everyone, not just the driver Cargo in the bed and cab tools, firewood, generator, coolers…

What no calculator can check: your actual axle weights. Stickers and percentages are the paper check — the real check is 20 minutes and $15.25 (2026 first-weigh price) at a CAT scale (truck stops have them), loaded for a real trip. If you're within 10% of any limit on paper, weigh before you buy.

Shareable summary

Why payload — not tow rating — is the number that decides

A modern diesel pickup might advertise a 25,000 lb fifth-wheel tow rating while its door sticker shows 3,000 lb of payload. A 12,500 lb fifth wheel puts roughly 2,750 lb on the pin at 22% — add a 200 lb hitch and two adults, and that "half-capacity" trailer has already overloaded the truck. The tow rating never entered the conversation.

That's not an edge case; it's the normal case. Pin weight lands directly in the bed, so fifth wheels consume payload about twice as fast (per trailer pound) as bumper-pull trailers. It's why the forums are full of people who bought the truck the dealer said "tows 27k" and discovered it can't properly carry the pin of a 13k trailer. Full explanation here.

The honest rules this calculator follows: trailer weight defaults to GVWR (loaded), never dry weight; pin weight defaults to 22% (not the brochure's dry hitch weight); your door sticker outranks any chart, including ours.

Checking a travel trailer instead?

Bumper-pull math is different — tongue weight runs 10–15% and a weight-distribution hitch changes the hardware. Use the travel trailer calculator.