The Chevy Silverado is a workhorse of a truck, and the 2018 model is no exception. When it comes to towing and hauling, the Silverado is a reliable choice. But to make sure your trailer is properly connected to your truck, you need to have the right wiring setup. In this article, we’ll cover everything you need to know about the 2018 Silverado trailer wiring diagram.
Understanding Trailer Wiring
Before we dive into the specifics of the 2018 Silverado trailer wiring diagram, it’s important to have a basic understanding of trailer wiring. Every trailer has a set of lights (typically brake lights, turn signals, and running lights) that need to be connected to the towing vehicle’s electrical system. This is done through a wiring harness that connects the trailer to the vehicle.
In order to properly connect your trailer to your Silverado, you’ll need to have the right wiring harness installed. Your trailer may have a 4-way, 5-way, 6-way, or 7-way connector, depending on the number of pins on the connector. The wiring harness on your Silverado will need to match the connector on your trailer.
4-Way Connector
A 4-way connector is the most basic type of trailer wiring setup. It has four pins and is typically used for small trailers that don’t have brakes or other advanced electrical features. The four pins on a 4-way connector are:
| Pin | Function |
|---|---|
| 1 | Ground |
| 2 | Left turn/stop |
| 3 | Right turn/stop |
| 4 | Taillights |
To connect a 4-way connector to your 2018 Silverado, you’ll need to purchase a wiring harness that matches your trailer’s connector. The harness will typically come with detailed instructions on how to install it.
5-Way Connector
A 5-way connector is similar to a 4-way connector, but includes an extra pin for the electric brake signal. If your trailer has brakes, you’ll need a 5-way connector to properly connect it to your Silverado. The pins on a 5-way connector are:
| Pin | Function |
|---|---|
| 1 | Ground |
| 2 | Left turn/stop |
| 3 | Right turn/stop |
| 4 | Taillights |
| 5 | Electric brakes |
To connect a 5-way connector to your 2018 Silverado, you’ll need to purchase a wiring harness that matches your trailer’s connector. The harness will typically come with detailed instructions on how to install it.
6-Way Connector
A 6-way connector includes all the same pins as a 5-way connector, but also includes a pin for the backup lights. If your trailer has backup lights, you’ll need a 6-way connector to properly connect it to your Silverado. The pins on a 6-way connector are:
| Pin | Function |
|---|---|
| 1 | Ground |
| 2 | Left turn/stop |
| 3 | Right turn/stop |
| 4 | Taillights |
| 5 | Electric brakes |
| 6 | Backup lights |
To connect a 6-way connector to your 2018 Silverado, you’ll need to purchase a wiring harness that matches your trailer’s connector. The harness will typically come with detailed instructions on how to install it.
7-Way Connector
A 7-way connector is the most advanced type of trailer wiring setup. It includes all the pins found on a 6-way connector, but also includes a pin for the auxiliary power supply. This is typically used to power the trailer’s interior lights and other accessories. The pins on a 7-way connector are:
| Pin | Function |
|---|---|
| 1 | Ground |
| 2 | Left turn/stop |
| 3 | Right turn/stop |
| 4 | Taillights |
| 5 | Electric brakes |
| 6 | Backup lights |
| 7 | Auxiliary power |
To connect a 7-way connector to your 2018 Silverado, you’ll need to purchase a wiring harness that matches your trailer’s connector. The harness will typically come with detailed instructions on how to install it.
2018 Silverado Trailer Wiring Diagram
Now that you understand the different types of trailer wiring setups, let’s take a look at the 2018 Silverado trailer wiring diagram. The diagram below shows the standard wiring setup for a 7-way connector on a Silverado:
As you can see, the diagram includes all the pins we discussed earlier. Pin 1 is the ground, pin 2 is the left turn/stop, pin 3 is the right turn/stop, pin 4 is the taillights, pin 5 is the electric brakes, pin 6 is the backup lights, and pin 7 is the auxiliary power.
If your trailer has a different connector (4-way, 5-way, or 6-way), you’ll need to purchase a wiring harness that matches your trailer’s connector. The wiring harness will come with detailed instructions on how to connect it to your Silverado.
FAQ
Can I tow a trailer without a wiring harness?
No, you cannot legally tow a trailer without a wiring harness. Your trailer’s lights (brake lights, turn signals, and running lights) need to be connected to your towing vehicle’s electrical system to ensure other drivers can see your trailer at night and during inclement weather.
How do I know which wiring harness to buy?
You’ll need to know which type of connector your trailer has (4-way, 5-way, 6-way, or 7-way) to determine which wiring harness to buy. The wiring harness will come with detailed instructions on how to connect it to your Silverado.
What if my trailer has special electrical features?
If your trailer has special electrical features (such as a hydraulic brake system or electric over hydraulic brakes), you’ll need to purchase a wiring harness that is specifically designed to handle those features.
Can I install a wiring harness myself?
While it is possible to install a wiring harness yourself, we recommend having it installed by a professional to ensure it is done correctly and to avoid any potential damage to your Silverado or trailer.
What if my Silverado already has a wiring harness installed?
If your Silverado already has a wiring harness installed, you should be able to connect your trailer to it using the appropriate connector. If you’re not sure which connector to use, consult your Silverado’s owner’s manual or contact your local Chevy dealer.
