Best Wiring Options for Towing a 5th Wheel Trailer

Published 03/02/2017

Products Featured in This Question

Hopkins Endurance 5th Wheel/Gooseneck 90-Degree Wiring Harness with 7-Pole Plug

(869)

$84.43

7-Way Pre-Wired Car Connector, 7' Lead

(73)

$80.52

7-Way Connector 7' Loop

(156)

$55.67

Deka Heat Shrink Butt Connector - 12-10 Gauge - Nylon Insulation - Yellow - Qty 10

(1066)

$12.75

Hook Probe Circuit Tester

(58)

$12.00

Quick Splices - Self-Stripping Connector - Closed Port - 10-12 Gauge - Yellow - Qty 1

(49)

$2.83

Question:

What options do I have to plug in my 5th wheel trailer to my truck? Do I have to use the socket at the bumper? Is there something easier?

asked by: Bill

Expert Reply:

You have a few options when it comes to 5th wheel wiring for your truck. Most trucks come with factory 7-way trailer connectors at the bumper. If your truck has a factory 7-way, then I recommend installing a 5th wheel wiring harness like the Hopkins Endurance 5th Wheel Harness, # 41157. In-bed harnesses provide a quick and easy connection point in the bed, so you don't have to modify the existing trailer harness to make it longer or use an extension.

This harness has a 90-degree plug, so it is easy to install in the side wall of your truck bed and it comes with plug-in style connectors to tee into the back of your factory 7-way. Check out the installation video I attached on a Chevy Silverado. This installation will apply to any full-size truck with a factory 7-way.

I've attached a link to all of our 5th wheel wiring harnesses for you to check out.

If your truck does not have a factory 7-way trailer connector, or it does not have the round plug-in connection behind the 7-way, you could splice a 5th wheel harness into the wires using part # 20023. You can splice right into the factory trailer harness by using butt connectors like part # DW05745-10, or quick-splices like part # SWC501915-1. The heat shrink butt connectors are the better long-term solution.

Keep in mind, when splicing, it is important to splice function to function, not color to color. The functions for the wires on this harness are as follows.

Yellow: center auxiliary/reverse
Green: tail and license lights
Brown: right turn and stop lights
Blue: electric brake
Black: battery charge
Red: left turn and stop lights
White: ground wire

You should test the factory wiring before making any splices because the colors probably won't match. To test each wire, I recommend part # PTW2993.

If you don't want to deal with the installation of an in-bed harness and want to save some money, then you will want to take a look at a 7-way extension to your bumper using our Draw-Tite 7 ft Extension, # 20027. This will provide plenty of slack when turning, so you don't have to worry about the harness snagging or pulling out of the socket.