2010 GMC Sierra 1500 Crew Cab Owner's Manual - Page 74

4. If equipped with a shoulder belt height adjuster, move it to the height that is right for you. See "Shoulder Belt Height Adjustment" later in this section. To unlatch the belt, push the button on the buckle. The belt should return to its stowed position. Before a door is closed, be sure the safety belt is out of the way. If a door is slammed against a safety belt, damage can occur to both the safety belt and the vehicle. 5. To make the lap part tight, pull up on the shoulder belt. It may be necessary to pull stitching on the safety belt through the latch plate to fully tighten the lap belt on smaller occupants. 2-32