Auxiliary truck lighting performs an important task, whether it’s to light the way in inclement weather conditions or provide much-needed additional lighting on the trail. It’s also become a fashion accessory for some as LED lighting has now been incorporated into grilles, grille guards, bull bars, and other accessories.

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How to Choose Auxiliary Lights for Trucks

What exactly are auxiliary lights?

These lights work in conjunction with your stock lights to provide added visibility. There are three basic types of auxiliary lights: fog lights, driving lights, and off-road lights. In addition, there are various types of off-road lights. Each of these lights uses a different type of light beam pattern to create optimum lighting for its intended purposes.

Fog lights are used for poor weather conditions such as rain, fog, or mist, or anywhere you may need additional lighting for safety. They create a wider, lower light beam that projects downward onto the road. This light pattern avoids the water droplets in the fog or rain, creating less glare and better visibility.

The Society of Automotive Engineers (S.A.E.) has developed a standard system for fog light mounting. The organization recommends mounting fog lights 10-14 inches above the ground and then testing the angle of the beam at 25 feet. The top of the beam should be about four inches below the center of the lamp itself (see diagram A below).

Driving lights, when used in conjunction with regular lights, allow you to see further into the distance. To prevent blinding oncoming motorists, the S.A.E. has also developed a method for mounting driving lights. The lights should be mounted 14-30 inches from the ground and then tested at 25 feet. The beam should be angled down to a spot about 1.5 inches below the center of the light’s original hot spot (see diagram B below).

Off-road lights provide added light for trails and other rugged terrain. They’re usually made from materials like ABS plastic, aluminum, and steel and are mounted in a higher position to create further reach.

Off-road lights can be had in many sizes and configurations. You can purchase individual off-road lights or complete light bars from companies like KC HiLiTES, Rigid Industries, and more. There are a couple different off-road lights to choose from:

Flood lights are great for camping or other recreational purposes because they light a wide area. They use a specially shaped lens to create a wide light pattern, especially when mounted high.

Spot lights provide a concentrated beam of light over a long distance. That makes them ideal for off-roading because they can shed light on unpredictable terrain and be adjusted by hand to focus on certain areas. Neither flood lights nor spot lights should be used for highway use.

In addition to the light pattern created by each of the lights above, bulbs also play a pivotal role in an auxiliary light’s effectiveness. Common choices are:

Halogen: A halogen bulb uses a filament which is contained inside a vacuum so it burns at a higher temperature and generates a brighter light than incandescent lights.

HID (High Intensity Discharge): HID lights use Xenon gas, which produces an extremely intense, white light. At the same time, they consume much less power than typical halogen lights, making them a popular choice.

LED (Light Emitting Diodes): LED technology emits a small area of spectrum light to create different contours and colors. These lights are bright yet require low power consumption and offer a long service life. Although you’ll notice LED lights in many auxiliary lights, you can also find LEDs in headlights and taillights.

Popular Auxiliary Off-Road Truck Lighting Options

KC HiLiTES Daylighters

kc hilites daylighter off road lights
(Image/Summit Racing)

Probably the most well known, off-roading lights, KC HiLiTES Daylighters are long-range lights that use a traditional H3 halogen bulb and reflector setup to deliver bright light. Plus, you get those iconic smiley face light covers.


KC HiLiTES LED SlimLites

(Image/Summit Racing)

Another popular choice from the KC HiLiTES lineup, SlimLites have a sleek, flat profile and a two-axis mount for easy, accurate aiming on the trail. They also have stone guards for added off-road protection.


Rigid Industries D-Series Dually Lights

rigid led light pods
(Image/Summit Racing)

LEDs come in many different configurations. These D-Series Dually Lights stack the bright, highly efficient LEDs a square design and sell the lights in pairs so you have multiple mounting options.


Hella ValueFit LED Light Bars

(Image/Summit Racing)

Hella ValueFit light bars are a budget-friendly way to add a ton of illumination to your ride. The bars are encased in die-cast aluminum housings with stainless steel brackets. Given their modular design, you can purchase several to tie together into a single, powerful lighting array.


Rigid Industries E-Series LED Light Bars

rigid led light bar
(Image/Summit Racing)

Available in lengths up to 50 inches, E-Series LED light bars project twice the light, turn on quickly with no warm-up, won’t drain your batteries, and offer 50,000-plus hours of life! They’re built with 6061 aluminum extrusions and feature a durable UV powdercoated finish.

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Author: David Fuller

David Fuller is OnAllCylinders' managing editor. During his 20-year career in the auto industry, he has covered a variety of races, shows, and industry events and has authored articles for multiple magazines. He has also partnered with mainstream and trade publications on a wide range of editorial projects. In 2012, he helped establish OnAllCylinders, where he enjoys covering all facets of hot rodding and racing.