How To Install Fifth Wheel Hitches?

Trailers with hitches installed

You can pay around $100 to $200 for a professional to mount a fifth wheel hitch on the bed of your truck. But why on earth would you do that if you can do it for free? That’s right! No costs other than sweat and time. Before you install a fifth wheel hitch, take note of this inventory:

Components, Tools & Resources

Main components:

  • Fifth wheel hitch (with a slider)
  • Rail kits (with steel brackets)

Mechanical resources:

  • Drill bits (17/32 inches)
  • Drill spacers
  • Bolts (5/8 inch for the 4-bolt rail or 1/2 inch for the 10-bolt rail)
  • Washers (the size of flats and nuts proportionate to the bolt)

Tools of the trade:

  • Wrench (5/16 inch head for 5/8 inch bolt or 3/4 inch head for 1/2 inch bolt )
  • Ratchet (5/16 or 3/4 inch drive)
  • Torque wrench (85 to 120 ft. lbs)
  • Drill (with a handle)
  • Center punch (spring-loaded)
  • Disc magnet
  • Colored marker
  • Tape measure
  • Jack lifts (optional)
  • Fish wire bolt leader (optional)

Now that we pretty much made a checklist of the hardware stuff you will need, let’s move on to the installation process. Some people would prefer to apply all these steps one rail assembly at a time or complete the whole thing at once.

Mounting the Fifth Wheel Hitch

Step 1: Preparation

Like many auto-repair tasks, you may need to elevate your pick-up truck for easier observation and movement during the fifth wheel hitches installation. It’s safer to do it in a garage shop with quality lifts but if you prefer to just jack it up independently, never do this task on a soft surface like a garden soil or asphalt. Being crushed by a 6,000 lbs vehicle is never part of the plan. Preparation also includes removing the inner fender wells and the rear tires.

Step 2: Measurement

Every fifth wheel hitches installation is guided by a detailed instruction manual which, in principle, prescribes the placement of the trailer’s pin box frontward from the truck’s wheel axle. With your tape measure and colored marker, you can adjust and determine the positioning of the first of the two rails (either the front or the rear). The position of the second rail is easier to determine once the perpendicular legs of fifth wheel hitch are latched onto them. Don’t forget to mark the exact points on the truck bed that’s visible through the rail’s holes.

Step 3: Checking Obstacles

The main reason for the thorough and painstaking preparation before you install a fifth wheel hitch is for you to get a clearer view of the truck’s rear underbelly. Before punching holes through the bed, you need to make sure that the vital obstacles (e.g. fuel lines, electrical wires, or exhausts) are out of the way.

Step 3: Drilling

Remember the points you have marked through the prescribed rail holes? That’s exactly where you will drive the first drill bits. Using your spring-loaded center punch, you can create a precise dent on the surface of the truck bed in order to make the drilling easier.

As soon as the first holes are done, you can now start adjusting the position of the initial steel brackets that adjoin it with the outer side of the vehicle frame. The disk magnet can help secure the position of the bracket precisely where its upper hole matches the punctured truck bed.

Granted, not all fifth wheel brackets are compatible with the vehicle frames. If the precise placement of the frame bracket has no outlet, you may need an extra drill bit to punch through its thicker surface.

Step 4: Bolt & Lock

After drilling the specific number of holes, it is time to attach the rails and the brackets. Steel drill spacers help level the gaps and prevent the beds from collapsing when you put bolts through the hole. Next, fasten each bolt with a flat and nut washer and tighten it with the wrench and ratchet.

You can use a fish wire bolt leader in case the angle for adjoining the washers with the other side of the bolt proves too difficult. As soon as the rails and brackets are secured to the truck bed and steel frames, you can use the torque wrench to finally lock the nuts and bolts tight. Take note of these precise locking pressure scales:

  • 5/8 inch bolt = 85 ft lbs
  • 1/2 inch bolt = 100 ft lbs     

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