Types of 5th Wheel Hitch Installations

Installing a fifth wheel trailer hitch in your pickup truck bed or flatbed truck can be done using a few different hitch mount configurations, including

• Industry Standard Rails

• Gooseneck Mount

• Puck System Installations

• Using Only a Gooseneck Hitch

Industry Standard Rails

At the advent of fifth wheel hitches many years ago, the industry leaders at the time got together and developed a standard mounting system of rails mounted across the bed in the back of the truck. 

These "industry standard rails" or "ISR" for short were designed with multiple slots. This enabled users to mount any hitch, whether they purchased a Reese fifth wheel hitch, a Curt 5th wheel hitch, or another make.

Industry standard rails are mounted to the truck bed with one 21-15/16" behind the other. They are generally mounted between the wheel wells on either side of the axle below. This is because you want the payload tongue weight of the fifth wheel trailer to be directly above the axle for proper load bearing and road stability. 

Fifth Wheel Hitches have two different stances. A narrow stance has the mounting points 20-1/2" wide, and a wide stance has them 29" wide. ISR's have mounting slots at both locations. They also have a narrower set of slots at 10". 

These are used to mount a plate for a gooseneck hitch ball mount. The front and rear legs on an ISR hitch, will, of course, be the 22 inches on center between the two rails. 

The base rails are secured to the frame of the truck using a vehicle-specific under-bed bracket kit. We have bracket kits for a wider variety of truck applications. Many are fabricated to use the pre-drilled holes in the truck frame, so you do not have to do any drilling to install the hitch in the truck box.

Be sure that the base rails you purchase are compatible with the fifth wheel bracket kit for your truck. As far as your hitch selection goes, these rails can fit hitch brands like Curt, Draw-Tite, Hidden Hitch, Valley, Husky Towing or Reese 5th wheel hitches.

Remember, if you have a truck bed liner that is other than a sprayin bed liner, you will have to cut notches out of the liner to install the rails.

There are also removable fifth wheel hitch mounts that are anchored to a gooseneck hitch below the truck bed. The rail portion of these mounts present the Industry Standard Rail configuration to mount your hitch. These allow you to remove the mount when you are not towing so that you have a flatbed without any obstructions for stowing cargo, etc. They also permit you to mount a hitch with an ISR configuration.

Puck System Installations

Some late model trucks have a built-in fifth wheel mounting option referred to as a fifth wheel "prep" package. These can also be called a puck system because the feet of the hitches designed for this configuration look like hockey pucks. These pucks get inserted into pre-cut holes in the truck bed to receptacles below. They are then locked in position with levers and secured with hitch pins.

You won't need a hitch bracket system if you have a puck system installation, because the frame brackets are already built in.

Here is an image of a truck with a factory-installed puck system. Note that it also has a built-in hole for a removable gooseneck hitch in the center of the configuration.

Here is an example of a hitch installed using a puck system. Note how clean the bed looks.

Gooseneck-Mounted Fifth Wheels

Some fifth wheel hitches use a gooseneck hitch installed below the bed for their mounting structure. This has the advantage of giving you a choice of towing options. If your job requires you to tow a gooseneck work trailer, you have the hitch built into the truck already.

When it's time for vacation or trips with the family, you can simply place your fifth wheel hitch on top of the gooseneck hitch ball. The hitch will have a built-in ratcheting system allowing you to tighten the hitch down onto the truck bed floor. This tightening down means that you can mount on a single point without the hitch turning in the truck bed.

Here is the B&W Companion Fifth Wheel Hitch fully installed in the gooseneck receptacle.

Most modern gooseneck hitches have the option of removing the hitch ball, turning it upside down, and storing it in the ball mount. This leaves the bed clear of obstructions.

Using Only a Gooseneck Hitch

If you want to use only a gooseneck hitch to tow your fifth wheel you can consider a couple of options. 

Pop Up Towing Products offers a fifth wheel to gooseneck adapter that mounts to your fifth wheel pin box and presents a gooseneck coupler on the bottom end. This allows you to connect the fifth wheel trailer directly to a gooseneck hitch. 

This is especially helpful if you have a very heavy trailer. Gooseneck hitches and the 5th wheel to gooseneck adapters both have higher towing capacity weight ratings than most fifth wheel hitches. 

The other option to tow using only your gooseneck hitch is to purchase a replacement pin box with a gooseneck coupler installed:

There are several versions of these gooseneck pin boxes made to fit the mounting hole configuration of the pin box you are replacing.

The downside to connecting directly to the gooseneck ball is that the connection will be more rigid, resulting in a rougher ride. But these options are less expensive than a full fifth wheel hitch setup, especially if you already have a gooseneck hitch or fifth-wheel prep package installed.

Getting the Right System

Not all systems are compatible with all pickup trucks. Consult with an RV Part Shop parts specialist who has the tools to find the fifth wheel hitches for sale and mounting systems that will work with your tow vehicle.

In addition to the year, make and model of truck you have, we will need to know the Gross Vehicle Weight Rating (GVWR) of the fifth-wheel trailer. This will allow us to recommend only hitches that have a sufficient towing capacity.

If you have a short-bed truck, you might also need to consider the need for a slider hitch. See our article Do I need a Slider Hitch to Tow a Fifth Wheel? for help determining whether a fifth wheel slider hitch is necessary for your application.

Short-bed trucks, including most crew cabs, need more clearance between the truck rear window and 5th wheel trailer nose, particularly when turning. A sliding 5th wheel hitch provides this added clearance. 

Getting the Right Advice

RV Part Shop can offer 5th wheel hitches for sale. We also offer fifth wheel hitch rails, and fifth wheel mounting brackets for sale, including:

• Reese Fifth Wheel Hitches

• Demco Hijacker 5th wheel hitches

• Curt Fifth Wheel Hitches

• Pullrite Fifth Wheel Hitches

• B&W Patriot Fifth Wheel Hitches

• B&W Companion Fifth Wheel Hitches

All these hitches, rails, and bracket kits come with installation instructions to assist you with a successful installation. Follow them carefully when installing a 5th wheel hitch.

Be sure and consult with one of our RV hitch specialists for advice on configuring the best solution for your fifth wheel towing needs.