When it comes to towing a 5th wheel trailer, there are some terms that you must learn and understand. Your safety on the road depends on it. One such thing is being able to answer the question…
What is pin weight capacity?
The pin weight capacity is how much weight can press down onto the 5th wheel hitch installed in your truck bed. This number of pounds is the actual maximum weight that is safe to have pushing down on the hitch when towing a 5th wheel trailer. The recommended amount of pin weight ranges from 15 to 25% of the GTW (gross trailer weight).
There is a lot of confusing information floating around the internet about this. Often it is confused with pin weight capacities vs payload capacity which are two different things. So, let’s dispel all misconceptions about it.
Definition of Pin Weight Capacity
As I’ve said above, the pin weight capacity is the maximum force or weight the combination of your truck and 5th wheel hitch can carry, i.e. the maximum safe pin weight of a trailer for said combination.
Many articles on the internet forget the fact that hitch can be a limiting factor, and disregard to mention it.
While it is not all that common, it is possible to stumble on some rare 5th wheel hitch that has low capacity. Generally, hitches exceed the payload capacity of practically every truck available on the market.
But, you should know that some do not. And in such cases, the pin weight capacity is equal to the capacity of that hitch.
In all other cases, pin weight capacity is equal to unused payload capacity. So, let’s get into a detailed explanation of all these terms and the relations between them.
The pin weight is the force that a 5th wheel trailer puts on the hitch and truck’s bed when they are hitched. This is a very important figure, as it determines which exact truck can pull some specific trailer.
It is an actual weight, that can be measured, while the pin weight capacity is in a sense the budget that pin weight is using.
The pin weight capacity can be increased in case the hitch has a lower capacity than the truck’s payload. Which is very rare. But, the pin weight of a trailer can be increased or decreased by cargo management.
Move cargo closer to the hitch, inside the trailer, and it will go up. Move cargo in the other direction, and pin weight will follow.
When managing cargo inside your trailer it is very important that you keep the pin weight at between 15% to 20% of GTW.
GTW rating or Gross Trailer Weight is the actual weight of your trailer when it is ready to be connected to towing vehicle.
On the other hand, trailers like any other vehicle have Gross Vehicle Weight Rating or GVWR, which describes the maximum weight a trailer is allowed to have when loaded with cargo and passengers.
It is important to know the GTW of your trailer, because it first must never exceed the towing capacity of your truck, and also because 15% to 20% of it needs to be transferred to a hitch to make towing as safe as possible. And I will later explain what are those safety issues.
Difference Between Pin Weight and Payload Capacity
Many sources confuse the pin weight capacity and payload capacity of a truck. But they are two different things. Payload capacity is how much a truck can carry in its bed, while pin weight capacity is the maximum pin weight it can carry.
The difference between these two ratings is created by the weight of the actual hitch installed in the truck bed. So, if the hitch’s capacity is not a limiting factor, pin weight capacity is equal to payload capacity decreased by the actual weight of the hitch.
The same relation is between the actual pin weight and the actual payload. The weight loaded into your truck’s bed is the pin weight plus the weight of the hitch.
Difference Between Pin Weight and Hitch Weight
Pin weight and hitch weight are terms that describe the same thing, the weight of a trailer that is transferred to the hitch when towing. Another synonym is tongue weight. But, there is one important difference.
The pin weight is a term that describes only 5th wheel trailers, while hitch weight can describe a trailer of any type.
The towing capacity of a pickup truck is the maximum weight of a trailer it can tow. There are many technical and mechanical reasons why this limit exists, but the most important, in the case of the 5th wheel towing, is the truck’s payload capacity.
The payload capacity is a limiting factor of pin weight capacity, and because the safest towing of 5th wheel trailers is when the truck carries 15%-20% of the trailer’s weight, towing rating is always five times the payload capacity.
Or you can say that payload is always ⅕ of towing capacity. And this value you can find stamped on the information plate near the driver’s door.
Based on knowledge of the towing capacity of your truck, you can calculate its pin weight capacity. You need to divide this number by 5, and then subtract from it the weight of the hitch, which can be found in its spec sheet.
The 20% “rule”
For conventional towing the hitch weight should be kept around 10% of GTW, but for 5th wheel trailers, it can be as close to 20% as possible. And this should be done for the same reason, safety.
Trailers on the road behave similarly to pendulums, as you are turning left and right their inertia makes them want to swing left and right.
Will, it actually swing depends on how much of its weight is concentrated in its rear end. So, naturally, you would want as much of its weight to be in front, closer to towing vehicle.
But too much weight in front can create two problems, truck and trailer squatting and severe under steering.
The way to prevent all these three problems is to have 20% of the trailer’s weight loaded on the hitch.
To be able to safely tow a 5th trailer within the capacity of your pickup truck, you need to understand what is the pin weight capacity.
It is a specification of a truck that tells you what is the maximum pin weight of a trailer that is appropriate for it. It can be calculated when from the truck’s payload capacity you subtract the weight of the used hitch.
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(Featured image: jayco.com)