How To Install Lights Under A Truck [11 Steps To Follow]

You may want to up your game when it comes to your truck's overall look. Surely, you've considered a fresh paint job, big flashy rims, and new tires for your truck's new appearance. Leveling up a bit more by installing lights under your truck is a great idea too, especially for your off-road adventures. If you're not sure how to do it, no worries as we've compiled everything you need to know.

The steps to properly install rock lights under your truck include the following:

1. Test your rock lights.
2. Remove wheel well liners.
3. Position your rock light to your desired location.
4. Drill the marked holes.
5. Assemble the parts.
6. Drill holes in the truck for the wires.
7. Replace the wheel well liner.
8. Run the wires through.
9. Repeat the process for the other side of the truck.
10. Use extension wires.
11. Plug and test.

A bit overwhelmed will the numerous steps? Read further, and we'll help you clear out things as we elaborate on the topic. Aside from dissecting each step, we'll also answer the most asked questions with regard to lights under your truck. 

Installation Of Underglow Rock Lights

You can proceed with this light installation under your truck once you have prepared all the necessary materials and tools you will use in the project.

Things You'll Need

• Rock light pods
• Wires and extension wires
• Manual switch
• Allen wrench/key
• Control module/Bluetooth module
• In-line fuse holder
• Torque wrench
• Wirecutter set
• Power drill with drill bits
• Push-pin remover
• Pen/pencil
• A cellphone (to serve as a controller)

Step-By-Step Guide

Now that you're ready with everything you need to successfully install Underglow rock lights, prepare to follow these steps below:

Step 1. Test Your Rock Lights

Before doing the whole process of installation, it's always important to test your rock lights first before installing them. This is to save you energy and time from the hassle of redoing steps again.

Also, don't forget to install the app that controls the rock lights. This will enable you to control the color of the lights and will also serve as a switch.

Step 2. Remove Wheel Well Liners

Unfasten the screws using a torque wrench and gently remove the entire wheel well liner. Use a push-pin remover in case the liner doesn't detach easily. Place it on the floor so you can easily go about the next step.

Step 3. Position Your Rock Light To Your Desired Location

Using your rock light's base as a guide, set it in the location where you want to place the light. Once decided, mark the spot and the holes using a pen or pencil.

Step 4. Drill The Marked Holes

Using a power drill and a drill bit, pierce the two marked holes in the wheel well liner. For the center hole, since it is where you'll lodge the wires, use a bigger drill bit. 

Step 5. Assemble The Parts

Install the rock light pods on the drilled holes, including the wires, and tighten the screws using an Allen key/wrench. 

Step 6.  Drill Holes In The Truck For The Wires

Drill holes in the wheel well liner's location in your truck. These holes will serve as wire passages.

Step 7. Replace The Wheel Well Liner

Now, return the wheel well liner back to its original location. The wires should now be inserted into the passage holes in the truck and should be connected to the car's battery later. Use an in-line fuse holder to connect all the wires from each part. 

Step 8. Run The Wires Through

All the wires must be securely placed underneath the truck. As much as possible, don't let them hang loosely for safety and aesthetic reasons. Tie them up with a zip tie to keep them in place. To cut wires to the right length, use your wire set cutter.  

Step 9. Repeat The Process For The Other Side Of The Truck

Since you're done with the first part of the process, you may now repeat the same steps for the other side of the truck. Make sure to use an extension wire once you'll start installing the lights on the passenger side of the truck, this is to ensure that they'll reach the battery.

Step 10. Use Extension Wires

Since the passenger side is quite far from the truck's battery and the wire of the rock light pods are short, an extension wire is much needed. Again, use an in-line fuse to connect the wires. Once you've connected all the wires, run them up to the engine bay where the battery is located. 

Step 11. Plug And Test

When all the wires are in the engine bay, plug it in the battery. Turn the engine on to test if the lights work with the use of the controller app that's installed in your cellphone or with the manual switch. And if the lights work, then voila! You're good to go. 

Watch this video that will show you how to properly install lights under your truck:

How Difficult Is It To Install Underglow?

It is not that difficult to install an Underglow for your truck. As long as you have the right tools, the whole process is quite easy and doesn't need much mechanical skill to do the job. 

How Long Does It Take To Install Underglow On A Car?

Installing an Underglow on a car would take more or less ">5 hours to complete. Underglow kits usually come in an easy-to-install set and a user-friendly manual, but the whole process of drilling, connecting wires, and whatnot would take a while.  

Are Undercarriage Lights Illegal?

Undercarriage lights are legal in some states, however, they come with some restrictions. States like Arizona allow amber and white Underglow, and some allow any kind of Underglow color. Others prohibit any kind of flashy lights on the road like Michigan. Thus, the legality of Underglows depends on the state where you'll drive your vehicle to. 

What Underglow Color Is Legal?

Typically, red and blue lights are not authorized to be used by private cars or trucks, since these colors are usually used by police cars, ambulances, and fire trucks. Some states like Kansas and South Carolina don't allow red Underglow. Other states prohibit both red and blue under lights, while others allow red and prohibit blue. 

You may check out this post to know if your car meets the criteria of being road-legal: What Makes A Car Street Legal? [12 Elements To Consider]

How much does Underglow cost?

An Underglow kit would cost around $50-$100 and up depending on the brand, quality, and quantity of the lights. On the other hand, the hourly rate service for the Underglow installation would range from $45-$125/hour depending on the car or truck. 

Click here to find this rock light kit on Amazon.

Can You Turn Underglow On And Off?

Yes, you can turn the Underglow on and off using its ">switch or through a controller. 

Do Underglow Lights Drain Your Battery?

Underglow lights are usually made of LED lights. LED lights don't drain your battery even when the car is off since it has a very low voltage consumption. It even barely uses a lot of power while your engine is on.  

In Closing

Underglow lights under your truck are easy to install but would take approximately 5 hours to finish. First, make sure that you've tested all the lights and installed the needed app in your cellphone for the Bluetooth controller. Remove the wheel well liner and install the rock light pods. Drill holes and assemble all the rock light pod's parts.

Connect all the wires using an in-line fuse, and use an extension wire as needed. To secure that the wires won't hang and are in place, tie them using a zip tie or tape. Bring all the wires up to the truck's battery and securely plug them in. Test your lights by switching on the manual switch or using your cellphone as a controller.  

Before going, check this cool post to know more about trucks: How Long Should Tires Last On A Truck?