Does the Pin Weight of a 5th Wheel Trailer Count Towards the Payload Capacity

Published 02/12/2020

Question:

Approximately 20 of the weight of the trailer is positioned on top of your fifth wheel which adds to your payload capacity am I right or am I wrong? A 10,000 pound trailer would add approximately 2000 pounds of payload in your box Once it gets hooked up onto your fifth wheel? So if you have a 2500 pound payload capacity you would only have room for 500 more pounds correct? I am an over the road truck driver. My drive axles for my fifth wheel can support 34,000 pounds. part of that 34,000 pounds includes the weight of my trailer sitting on the fifth wheel .

asked by: Scott

Expert Reply:

You're correct that the pin weight of your trailer is going to take away from the payload capacity, since that weight is going to be over or slightly forward of the rear axle of your truck and also correct that it is typically around 18- 20% of the GVWR of the trailer. The payload also gives you 150-lbs that is not considered (the average male driver) so it's technically 150-lbs more than what it says.

If you have a 10000-lb trailer, the tongue weight should be around 1800-2000-lbs (you can find the pin weight on the spec sticker located on the king pin or on the trailer spec sticker); you will want to find this exact number because it's not always going to be precisely 20%. The key here is making sure that you're not putting much cargo in the front of the trailer so that you're not adding to the payload weight unnecessarily. If you've got a 2500-lbs payload capacity and 2000-lbs pin weight on your 5th wheel trailer, you can carry about 650lbs in your cab and truck bed (since you've got a built in 150-lbs for the driver that is not calculated into that 2500-lbs). Payload also does not include the weight of fuel, since it assumes that you already have a full tank of gas and all fluids topped off.

You're correct in your assumptions here, and in order to get the most accurate information on the capacities of your truck you'll want to know your trim package and transmission type, since I've seen information that says there are some trim packages with higher payloads/lower towing capacities.

expert reply by: Erik B