Pin weight, payload, and the number on the brochure

A fifth wheel feels stable because a lot of its weight sits on the truck. That is the feature. It is also the part that uses up payload.

The dry pin weight in a brochure is the trailer empty, or close to it. You do not travel that way. Water, batteries, a residential refrigerator, and a basement of camp chairs move the number. Some of that weight lands on the pin, and all of the pin lands on the truck's payload.

Payload is one pile of pounds

The door sticker payload is a single budget. Spend it on:

• people in the cab
• dogs, tools, and a cooler
• the hitch in the bed
• the pin weight of the loaded trailer

If the pin alone is close to the sticker, the truck is already done. There is no second payload hiding in the tow brochure. RigFix calls the result tight when little room remains, using a planning band we publish in the towing tool. That band is not a Ram rating and not a trailer rating. It is a way to say "you are close" before a scale says "you are over."

GCWR still includes the truck

Gross combined weight is the truck plus the trailer plus everything in both. A trailer GVWR that is under the truck's GCWR has not passed the test. The truck has to fit in the gap.

You can get a useful gap only if you know what the truck weighs as it will travel: fuel, people, and the gear that stays in it, trailer off the hitch. A CAT-scale style ticket is the ordinary way to learn it. Until you have that number, the towing check on this site refuses to fill one in. A guessed curb weight would look like a fact. It is not one.

Suppose you typed a payload of 3,800 lbs, a pin of 1,900 lbs, and 300 lbs of people and gear. The pin fits, and about 1,600 lbs remains. Those figures are an illustration of the arithmetic, not a claim about any Ram. Your sticker is the input.

Suppose the same illustration used a GCWR of 25,000 lbs and a trailer GVWR of 15,000 lbs. The gap is 10,000 lbs, and it has to hold the truck. If you then enter a scale weight of 8,200 lbs, the combined number is 23,200 lbs, leaving 1,800 lbs. If you do not have the 8,200, RigFix stops at the gap and says the check is unfinished.

A sanity check, not a spec

Loaded fifth-wheel pin weight is often roughly 15 to 25 percent of the trailer's weight. If the pin you typed is 8 percent of GVWR, you may be holding the brochure's dry hitch number. If it is 40 percent, something is off, or the trailer is loaded in a way you should fix before a mountain grade. The towing tool flags both. It does not "correct" your number.

A scale settles it. Weigh the truck alone, as you travel. Weigh the combination. The pin is the difference in the truck's weight with the trailer on and off, if you weighed it the same way. Compare that pin to payload. Compare truck plus trailer to GCWR. Then believe the scale over the brochure.

If you buy a scale or a hitch through a paid link, that link will be marked. An example of the markup, which is not a real offer, sits below.

Example scale affiliate (demo link, not a real merchant) (affiliate link)

RigFix does not certify a tow. If the sticker math says you are over, you are over on the numbers you entered. Change the load or the plan.