Have you noticed that the Ford Raptor, Ram 1500 TRX, and Toyota Tundra TRD Pro all have yellow-colored lights set into their grille? This is not some fad among 4×4 trucks but a government-legislated feature. These grille lights are related to the amber-colored light pods on top of semi truck’s roofs.

Why do semi trucks have yellow lights on their roofs?

The row of amber-colored light pods on the roof of a semi truck tractor are called marker lights, or clearance lights. They warn motorists that a vehicle wider than 80 inches is approaching. These lights always come with corner markets to show the full width of the oversized truck.

Yellow/amber marker lights have a simple purpose: warn drivers that a big rig is approaching. The corner markers make sense: they illustrate the width of the truck in the dark, and show other motorists how much clearance is available.

The row of yellow lights along the roof of a semi truck cab is part of the same marker set. The law states that they must be mounted as high as reasonably possible–according to Jalopnik.

These upper lights are a sort of visual code to identify the big rig. Their placement on the top of the semi truck also helps other truck drivers navigating truck stop parking lots spot the nearby truck.

Why do some off-road pickup trucks have yellow lights in their grilles?

When Ford’s Special Vehicle Team (SVT) turned an F-150 into the Raptor, they modified its suspension to set its wheels wider apart. This increased track bumped the resulting truck above the magic 80 inch width and meant it needed to come with marker lights–just like a semi truck.

Ford’s approach to legally-required marker lights was unique: the automaker made the amber marker lights into part of the Raptor’s signature look. Head designer Tim Liu took inspiration from fighter jets, video game vehicles, and even Marvel’s Iron Man before setting the Raptor’s marker lights into its grille and headlights surrounds.

The resulting Raptor has amber markers on its outer corners, signaling its true dimensions to other drivers. But instead of rooftop markers, Liu decided to set its top row of marker lights in the grille.

Other 4×4 trucks imitated the Raptor’s marker lights

When Ram launched its 1500 TRX, the Hellcat-powered 4×4 featured lights very similar to the Raptor. The Ram also had a widened track and required marker lights, and Stellantis decided the Raptor’s in-grille markers were an excellent solution. Then Toyota unveiled an all-new TRD Pro that made more torque than the V6 Raptor. Toyota also incorporated Raptor-like marker lights.

It is obvious that these yellow, in-grille lights are the industry standard for the new off-road supertrucks.

Next, learn why some semi truck tires don’t touch the ground.