Fog Light Buyer's Guide

Buyer’s Guide to Fog Lights


When fog, snow, rain or dust causes visibility problems behind the wheel, turn on those fog lights to ease the drive


 By Peter D. DuPre

One truth about both the landscaping and contracting businesses is owners are firing up their pickups in the pre-dawn hours to go to work and often arriving back home well after sunset.

The differences between light throw and spread are clearly illustrated in this drawing. Note that fog lights throw short and wide to light the roadway close to the vehicle. (Illustration by P.DuPre/AutoWord)

We accept the long hours as the nature of the business. But unfortunately those pre-dawn and late-evening commutes often mean dealing with hazards such as rain, snow, dust or fog.

Dealing with adverse driving conditions like these at any time is a hassle, but light levels at their worst add an element of danger most of us could do without.

So what do you do when Mother Nature is trying her hardest to make driving miserable?

The typical driver switches on the factory fog lights – if their pickup is so equipped – thinking they will provide proper illumination for safe driving.

But as anyone who has flipped on those fog lights knows, most simply aren’t up to the job; they are more ornamental than functional. (Apparently pickup designers often think more about style and cost cutting than they do about safety and practicality.)

Aftermarket fog lights are a different story.


Aftermarket (AM) fog lights are available in a variety of sizes, with different lens designs, bulb types and housings. One typically gets what they pay for when it comes to functionality and durability.

The cheapest of these are often packaged in thin metal buckets or plastic housings and use a sealed-beam filament headlamp bulb for illumination. They’ll last about 200 hours, or so, of continuous use.

If your pickup is your rolling office or primary work truck, don’t waste the time or money on them. Such old-style lights just don’t deliver adequate beam spread or brightness for serious use.

Further up the fog-light performance (and cost) ladder are those with quartz-halogen bulbs, which are usually packaged in ABS plastic or Lexan-type housings. Halogen lights deliver a quality beam pattern with sufficient brightness for fog-light use.

While these deliver a much hotter and brighter light than that of a standard filament bulb and last up to 400 hours or so of continuous use, they are prone to filament breakage from vibration. Continued use in rough terrain or over rock and gravel roads can shorten that bulb life considerably.

Near the top of fog-light performance for both longevity and light output are the high-intensity-discharge (HID) lights.

Unlike filament bulbs, HID lights do not have a filament.

Instead, an internal or external ballast builds up the power to create light when an arc jumps between two electrodes, stimulating a special mixture of Xenon gases to produce a brilliant, almost blue-white light that’s about three times brighter than a halogen bulb emits.

Because there is no filament, HID lights are less prone to vibration damage and last much longer (about 4,000 hours of continuous use) than standard or halogen bulbs. One pays 2 to 3 times more for these bulbs.


The most recent technology, though, revolves around LED fog lights.

Although the LED (light emitting diode) was invented in 1927 and first used commercially in 1969 (mostly for calculators and wrist watches), it has only been over the past few years that they have finally come into their own for use in automotive lighting.

A few years ago such lights were prohibitively expensive. Now the marketability of these long-lasting, brighter and cooler burning lights has resulted in the prices coming way down, making them competitive against HIDs.

The key to the brightness and light output is the size and number of crystals used, the makeup of the crystals, the design of the epoxy surrounding the crystal and the lens used to direct the light.

LEDs are also a lot more reliable than traditional automotive lighting options.

According to the folks at Vision-X, expected life cycle of an LED automotive light is about 50,000 hours versus the approximately 400 hours of other comparable lights.

This means, effectively, in most cases a LED automotive light is a lifetime purchase.

For commercial use, this is a double bonus since the LED also uses only about 85-percent of the energy required to operate quartz halogen or HID systems, saving wear and tear on batteries and alternators.


Really good lights of any type have to have lenses designed to focus the light into a flood, spot or, in this case, fog-pattern beam.

A properly-designed fog-light delivers a wide and relatively short (not more than 150 feet or so) beam pattern that is aimed low to increase road visibility near the vehicle during slow speed inclement weather driving.

It should also have a lens design that cuts off light above the vertical mid-way point so there’s no light reflecting back into the driver’s eyes.

This effect, called backscatter, is caused when up-angled light beams reflect off the moisture droplets in the fog (or from the snow, misty rain or dust), which is why a vehicle’s high-beams are totally useless under such conditions.

The low-angled fog light beams avoid this problem by aiming light downwards and improving near-vehicle visibility, but with enough light output to light the road 100 to 150 feet ahead.


A well-designed lens makes the difference between a fog light that actually does the job and an ornamental fog light that just looks cool. Lens color adds to that performance difference.

White (clear) is the more common lens, although amber and yellow lenses work better in rain, snow and fog.

Stay away from blue spectrum lights (color temps above 6,500 degrees Kelvin), found in many HID lamps offerings, as the eye doesn’t respond as well, especially at a distance.

As for power, a higher watt output produces a brighter, more penetrating beam. Run-of-the-mill bargain fog lights are typically rated 35 watts, while the better, higher-performance models can come with 100-watt output, or the equivalent in LED.

When you drive your pickup for business and spend a lot of time on the road in bad weather conditions, look for fog lights with an output of 55 watts or higher.


Fog lights work best mounted in, on or below the bumper (10 to 24 inches above the road surface) or anywhere below the center of the headlights, where their beam can cut just under that of the low-beam headlights.

The lights should be positioned closer together than the headlights (approximately 20 to 26 inches between them) and aimed so the cut-off line of the beam is about the middle of the low-beam headlights’ pattern.

The best way to aim the lights is to park the truck on a level surface 25 feet from a wall. Measure the distance between the center of the fog light and the ground.

Place a horizontal mark on the wall at that height. Visual aim is made with the top of the fog light beam about 4 inches below the lamp center at 25 feet with the lamp facing straight forward.

If you drive over a lot of narrow, winding country roads, angle the passenger’s-side light slightly to the right of the low-beam headlight’s center so the fog light illuminates even more of the road side.

Also make sure they are wired so they operate either independently and/or in conjunction with the low-beams to keep within the legal requirements.

Never use fog lights with high-beam headlamps or auxiliary driving lights as this can blind oncoming traffic. See the chart for a rundown on state regulations.


According to Bruce W. Smith, editor of ProPickup, fog lights have other practical uses in the construction and landscaping trades. 

In ProPickup’s auxiliary lights buying guide, Smith points out that when mounted on the rear bumper they make great backup lights and when installed higher up on a rack, the wide beam pattern makes for a serviceable work light.

Fog lights also work exceptionally well as a poor man’s portable flood light, too. Connect 20 feet of double-strand or twisted 14-gauge wire to a fog light with an auxiliary-type plug on the other end. Then the light can be used under the hood or truck or positioned as a light source for other work.


While using fog lights for an auxiliary lighting source when visibility is less than 400 feet is an aide to automotive safety, improper use can cause problems.

According to a study by the Society of Automotive Engineers (SAE) , while nighttime use of fog lights is high, driving conditions do not usually warrant their use.

Drivers often use the lamps to supplement head light brightness at night and to add a “cool” factor to their vehicles during daylight hours. According to Rob Camp – a Portland, Oregon, area automotive insurance agent – drivers using fog lights improperly can be a danger to others.

“Fog lights are designed to help drivers see and be seen when weather conditions severely reduce visibility,” says Camp.

“Running with lamps on when weather conditions are clear can have the effect of dazzling or temporarily blinding other drivers, which can lead to accidents. It is also a good idea to make sure that they are properly aligned.”

This is particularly true of work trucks, which often have a significantly higher ride height than automobiles, meaning that fog lights on those trucks could be shining directly into other driver’s eyes or their rear view mirrors.

So the rule of thumb here is if you can see farther than a football field down the road, keep the fog lights off.


KC HiLites SlimLite

Known for their off-road racing lights, KC Hilites’ new six-inch KC’s SlimLites ($280) have a 23-year (sans bulb) warranty and are an ideal fog light for contractors’ trucks. The SlimLite’s thin profile allows them to easily fit many popular brush guards, light bars, sport racks, OE and aftermarket bumpers. Optical quality glass lens, replaceable 100-watt H3 halogen bulb and precision polished reflectors generate a super bright fog-light pattern. Housings are available in a choice of brilliant chrome-plated or deep black powder coat finishes. The SlimLite kit contains two lights, ABS stone guards, plug-and-play wiring harness with relay and illuminated switch. For more info: (928) 635-2607 or

 VisionX Quad LED

When two fog lights aren’t enough for your Chevy Silverado, bolt in VisionX’s quad 5-inch-square LED fog light kit ($545). The Silverado Quad Fogs (#XIL-OE0711CSS1100) feature 10-watt LED bulbs with 50,000 hour lifespan, all packaged in a black aluminum housing and multi-volt 9-48V DC input. Each of the four lights is individually adjustable to provide optimum coverage. The bolt-on direct-to-factory mounting kit provides triple the light output of factory lights. For more info: (800) 994-4460 or


Purpose built for foggy conditions or foul weather, the IPF rectangular fog light kit (#840FYS/$216) from ARB 4Ă—4 Accessories is ruggedly built and designed for off-road and commercial use. Each 6.6- x 3.5- x 2.7-inch light has a hardened yellow glass lens in a rugged aluminum housing with an adjustable pendant-style mount. Light comes from an 85W High Performance H3 Bulb. The complete kit includes two fog lamps, white protective covers, snap-together wiring loom and relay and LED-illuminated toggle switch. The kit comes with a limited two-year warranty. For more info: (866) 293-9078 or

 Lightforce 170 Striker

The mid-size Lightforce 170 Striker ($329/pr) packages the same features as the small 140, but in a larger assembly and with a brighter, 12V 100-watt 2,000 hour bulb (at maximum wattage), making it perfect for use as either a fog or a driving light, depending upon filter. Kit comes with wiring harness, relay and fuse for easy installation. For more info: (877) 510-9204 or

Warn W650F

Designed to light the way through foggy, rainy, dusty or snowy conditions, the W650F (#82425/$225pr) fog light from Warn features large, 6.5-inch lenses and a broad 70-degree beam spread to provide full road coverage. The hardened clear glass lenses have a dichroic coating for a low-glare yellow light. Features include 55-watt H3 halogen bulbs, vaporized aluminum-over-steel reflectors for great light output, thin-profile powder-coated steel cases for excellent water resistance, and a wireless control switch for hassle-free installation. Each kit includes two lights, mounting hardware, wireless control, transmitter, wiring, rock guards and covers. For more info: (800) 543-9276 or

Warn W2030F

For applications where mounting room is tight, try a pair of Warn’s W2030F fog beams (#82415/$199pr). These compact lights measure just 2 by 3 inches, but the 55-watt halogen bulbs provide 66-degree bar-shaped beams of bright light, which are perfect for use in fog, rain, dust or snow. Features include impact-resistant hardened, blue glass lenses; durable vaporized-aluminum over die-cast aluminum compound curve reflectors for maximum light output; and lightweight, corrosion-resistant aluminum cases. A wireless control switch allows for easy installation without drilling through the firewall. For more info: (800) 543-9276 or

Pro Comp USA

The 4- x 6-inch amber fog light kit from Pro Comp (#9250/$41) offers quality performance at a bargain price. Each kit includes two lights with amber lenses and a complete wiring and switch kit. Optional protective covers are available. The 55-watt lights are packaged in a rugged, black ABS housing featuring multi-position mounting and positioning ability. For more info: (800) 776-0767 or

Lightforce 140 Lance

It may be small, but the 140 Lance ($280/pr) from Lightforce can be a wise choice if you need a high-performance fog light in a compact package. Off-road competition vehicles often install these as fog, winch, work or backup lights with special dispersion filters. Available singly or in pairs, each light is powered by a 12V, 75-watt Xenophot 4,000 hour bulb (at maximum wattage). 24V halogen bulbs are also available. Lightweight polycarbonate, glass-filled nylon composite construction assures that this light will stand up to the rigors of the jobsite and a Gore-Tex breather protects against moisture ingress. The 140s come standard with a clear, clip-on polycarbonate protective filter, but amber and yellow fog/dust lens filters are also available. For more info: (877) 510-9204 or

 VisionX OEM LED

Vision X’s LED fog lights (#XIL-OE0210DRUM4010) – a leader in LED aftermarket lighting – are a perfect replacement for the OE fog lights in today’s full-size pickups. VisionX’s OE 3-watt LED Technology produces three times the light output of the 35-watt factory fog lights and last up to 50,000 hours. Each light has a narrow beam pattern that provides a tight beam pattern for great distance while a polycarbonate “fog” lens can be snapped on for inclement weather use. For more info: (800) 994-4460 or

PIAA 520 Series

The six-inch-diameter 520 Series from PIAA has graced the fronts of many pickups and SUVs over the years because of its performance. The 520 Series ($330/pr) is available in both driving and fog lens configurations. Both versions feature rugged chrome or black steel housing and are available singly or in a kit featuring two lamps, wiring harness, relay, switch and mesh-type protective stone guards. The light uses an 85-watt H3 Ion Crystal for projection through a fog-patterened, hardended glass lens and delivers a full 80-degree side-beam spread for edge-to-edge road coverage. For more info: (800) 525-7422 or