Headlight adjustment is an important maintenance tasks on a vehicle. Maladjusted headlights can be just as bad as faulty headlights. Although every Chevrolet vehicle comes out of the factory with its headlights already adjusted, if you get in an accident, it may be necessary to adjust your headlights. Thankfully, headlight adjustment is a simple process on the 1999 Chevrolet Suburban, requiring only a few minutes to perform.
Park the Suburban 25 feet away from a blank wall. Make sure the headlights are facing the wall. Turn off the engine, but leave the keys in the ignition.
Turn on the headlights. Use a tape measure to measure the distance between the ground and the center of the headlights and compare that with the distance between the ground and center of the beams on the wall. If the bright spot of the headlights is not straight ahead, and at the same level of the center of the lens, the headlights will have to be adjusted.
Open the hood of the Suburban. There are two adjuster screws above each headlamp. The one closest to the outside adjusts the vertical alignment. The other adjusts the horizontal alignment. Use the Torx screwdriver to adjust the headlights to the desired position. Make sure the headlight beams are aimed below the center line on the wall, otherwise oncoming drivers will be blinded by the headlights.
Close the hood.
