GMC 16524812 Headlamp Assembly

To adjust a headlight, use spring-loaded screws for the beam headlights and Torx-head screw adjusters for composite headlights. You will need a blank wall, level floor beneath it; masking tape should be positioned vertically in reference to vehicle centerline and headlight centerlines on the wall. Also, a horizontal tape line may be positioned referring to the centreline of all headlights. The adjustments ought to be carried out while the vehicle is sitting level with half-full gas tank and no more than normal weight load inside it. When starting with low beam adjustment, place your high intensity zone two inches below the horizontal line but two inches to the right of vertical line coming from headlight. In order to raise or lower beam turn top adjusting screw clockwise or counterclockwise correspondingly while side adjusting screw is applied for moving light left or right. In High-beam mode, this concentrated brightness band should sit just below the horizontal line, centered vertically. After doing so then finally you can fix your lights as you see fit.