How to Install Truck Cab Lights: A Step-by-Step Guide & Legal Requirements

Introduction

Have you ever marveled at the striking row of lights atop trucks during nighttime drives? Much like cars rely on bright headlights for safety, heavy vehicles enhance visibility with cab lights. This article delves into the realm of cab lights, exploring their significance, functions, and installation methods. Whether you're a truck owner seeking an upgrade or simply curious, this guide will shed light on cab lights.

What are cab lights?

Cab lights, also known as clearance lights or roof marker lights, these auxiliary lights adorn the front roof of trucks, SUVs, trailers, and large commercial vehicles. Its design shapes are different, including triangular, conical, rectangular, etc., aiming to improve the visibility of the vehicle. Regulatory requirements dictate the number and arrangement of cab lights for vehicles over 80 inches in width. Of course, the specific number and arrangement of cab lights depends on the vehicle and the relevant regulations of the region.

What is the purpose of cab lights?

Even experienced truck drivers may not think much about the existence of these cab lights, but in fact, these cab lights are necessary for trucks. By understanding their function, you will know why they are mandatory.

• Identification function

Cab lights for truck enhance truck visibility in low-light conditions and poor weather, particularly on undivided roads. Evenly distributed cab lights can also broadcast information about the size and shape of a vehicle to other drivers. This can reduce the risk of friction collisions between two vehicles by anticipating the size of the body and allowing drivers to provide more room in advance for large trucks to pass in narrower road conditions than usual.

• Security function

In addition to making your vehicle more easily recognized by others, cab lights add an extra layer of protection to your vehicle's driving safety. When on dark foggy nights, the eye-catching cab lights can make your night driving task easier and prevent major traffic accidents.

• Visual appeal

There are currently a variety of cab lights on the market for people to choose from, especially LED roof cab lights are available in amber and white color options and different material color housings. Bright and high-quality cab lights can bring a new look to your vehicle. These high-quality roof lights allow truck owners to personalize their vehicle's appearance while ensuring optimal visibility.

Through the above functional description, the necessity of cab lights is obvious. Then installing cab lights is our main concern. 

How to install cab lights?

Some people will also be dissuaded by the troublesome process of drilling, but after understanding their installation tutorial, it is actually not difficult, just takes some time and patience. And with the advancement of technology, cab lights have also been introduced in wireless styles. Therefore, the cab light installation tutorial below is divided into two situations: wired and wireless.

Wired cab lights (Drilling)

If your truck already has OEM driving lights, upgrading to LED cab lights is a simple process, just remove your factory cab lights and bolt these in their original place. The red wire connects to the positive pole and the black wire connects to the negative pole.

But if your truck doesn’t come with cab lights, then congratulations, this is a great opportunity to personalize your vehicle. And here are the detailed steps for installing wired cab lights.

Preparation: Gather tools and create cab light base molds

Before installing the cab lights, you can prepare the following tools: cab light kit, tape measure, drill hole, signal pen, wire cutters, ordinary masking tape, electrical tape, screwdriver, silicone gel, etc. Then you can optionally use a piece of cardboard or white paper to copy the base of each cab light and the positions of the three holes for reference when marking and drilling later to prevent deviations in drilling.

Marking: Use masking tape to mark and find the center point on the roof

Use masking tape to protect the roof and mark the center point by aligning with the third brake light or windshield mirror. Measure one foot outward from center, then evenly space five cab lights between the drip rails, marking their positions with a pen.

Location Determination: Arrange and adjust cab lights for optimal placement

After placing the five cab lights in the marked positions, you can make unlimited check adjustments from the front of the car to determine your satisfaction with their placement.

Drill and Install: Follow the marked positions, drill holes, apply silicone, and secure cab lights

Remove the roof liner (optional), drill the holes accordingly to the cab light base template or the marked hole points, then place the cab lights and utilize silicone to treat the screw holes and bases to strengthen their seal. Finally, screw in the cab light with a screwdriver.

Wiring: Connect wires to the desired locations inside the vehicle

Finally, for the wiring part, you can choose to connect the wires to the roof lining or remove the screws of the sun visor, pass the wires through the screw holes, and then along the inside of the A-pillar to the skirting board and so on. In short, after introducing the wires into the car, select the wiring location according to the lighting operation mode you want, such as the headlights, instrument panel, skirting board, and other related plug wiring locations.

After completing the above steps, check that the cab lights are working correctly and then reinstall the remaining removed parts and you're done.

Wireless cab lights (No Drilling)

Some people don’t like to drill holes in the roof of trucks to install cab lights, and wireless cab lights (cab light no drilling) are just right for that. No wiring required, solar power supply and remote control device switch, and the installation process is also very simple. Let’s take a look.

Preparation: Prepare tools and arrange the installation location

Prepare the tools to be used such as tape measure, screwdriver, etc., then place the tape measure on the roof of the car, and distribute the position of each cab light unit according to the scale of the tape measure. (Of course, you can also refer to the center point confirmation method of wired cab lights to determine the pasting position)

Installation: Follow the distribution position, paste the base, install remaining accessories and secure cab lights

After determining the location of each cab light unit, tear off the 3M tape and stick it to the cab light base, then install the cab light bulb and cover, and tighten the screws of the cover. The installation process is complete.

Conclusion

Overall, proper placement and spacing of truck cab lights - whether wired or wireless - is crucial for clearly indicating your truck's dimensions.If you encounter any problems during the installation process, it is also recommended to consult a professional for professional installation guidance. Furthermore, with the purpose and benefits of cab lights explained above, you should be well aware of the necessity of having them, which is vital to ensure the safety of the truck driver and other vehicles. So if you are preparing to install them or considering upgrading your roof marker lights, get started now.

FAQ

Q: Can you put cab lights on any truck?

A: Of course you can. American law requires cab lights on trucks over eighty inches but it doesn't explicitly prohibit trucks under eighty inches from having them. So trucks of any size have the option to install cab lights.

Q: What color are clearance lights on a truck?

A: According to laws and regulations formulated by the U.S. Department of Transportation, “Front clearance lamps mounted on the front or on the side near the front of a vehicle shall display or reflect amber color.” However, the specific legal cab light color depends on the laws of the state where it is located. Apart from amber, cab lights are available in white and smoked housings, you can choose these two colors of cab lights according to your preference.

(By the way, side marker lights are also a type of clearance light. Understanding side marker lights will also help you ensure driving safety in blind spots. For more information, you can read this blog- ROAD-READY WITH SIDE MARKER LIGHTS: WHAT YOU NEED TO KNOW)

Q: When drilling holes in the roof of your car and you don't want to remove the roof liner, how do you make sure the drill bit doesn't go through the roof liner?

A: As a rule of thumb, you can drill only about a quarter of an inch. And to prevent drilling too much, you can use wire cutters to hold the drill bit in place about a quarter of an inch in, which will prevent you from drilling too deep and drilling out the roof liner and poking a big hole.

Q: What are wireless cab lights?

A: A wireless cab light (CAR OVER AMERICA) is a direct stick-on cab light that requires no drilling or wiring. It is powered and generates electricity mainly by absorbing solar energy. Its light on/off mode is controlled by a remote control unit, which allows us to operate these lights from inside the car or from a distance. But it is expensive at around 400 dollars. And it is doubtful that they will get a long-lasting charge in trucks kept in garages.

Q: Why do trucks have 5 lights on the cab?

A: It's not always 5 lights, it can be any number of lights which depends on your state's regulations. What's important is that they are mounted on the top of the truck. As they both approach each other on either side of a crest, the truck driver will be dazzled by the high beam of the car well before the car driver even knows that there is a truck coming. Those lights above the cab of the truck are there to alert car drivers to the fact that a truck is approaching and that the car driver should switch to a low beam.