How To Adjust Fog/Driving Lights
by Bruce W. Smith
But to get the most from the auxiliary lights – and to keep from blinding oncoming drivers – they need to be properly aimed.
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.
Fog lights should be positioned approximately two feet apart and aimed so the cut-off line of the beams 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 and adjust the lights so the top of the fog beam pattern is about 4 inches below the lamp center at 25 feet with the lamp facing straight forward.
Adjusting driving lights much the same way. But use their “hot spot” as the adjusting guide.
The driving light’s hot spot should be adjusted so it’s about 1.5 inches below the light’s centerline mark on the wall.