Why is a 5th Wheel Hitch is Installed Over or Forward of the Tow Vehicles Rear Axle

Updated 10/24/2011 | Published 10/22/2011

Question:

Why must the hitch be forward of the rear axle?

asked by: Ray P

Expert Reply:

When installing a fifth wheel hitch on a truck, the king pin will be centered over the rear axle or slightly forward of the rear axle. It will depend on the year, make, and model of vehicle and the size of the truck bed on where you will need to locate the fifth wheel hitch on your truck.

The reason the fifth wheel hitch is located at the rear axle or forward of the rear axle is that the pin weight of the fifth wheel is now pressing down between the cab and the rear axle, which will distribute the weight of the fifth wheel correctly over the rear axle of the truck, instead of behind the trucks wheelbase. This will allow the truck to carry a greater amount of weight and keeps the weight of the fifth wheel from raising the front of the truck so much that it causes handling and tire wear issues.

It also makes the fifth wheel easier to maneuver, like backing up or angle into parking spaces, since the hitch is closer to the turning wheels of the truck. It will also allow the fifth wheel to ride smoother.

I am including a link to a FAQ page on fifth wheels.

expert reply by: Jeff D