1998 GMC Suburban Owner's Manual - Page 56

To move the height adjuster down, push in at the word PRESS and move the height adjuster to the desired position. You can move the adjuster up just by pushing up on the shoulder belt guide. After you Inwe the adjuster to where you want it, try to n1ove it down without pushing in to make sure it has locked into position. Adjust the height so that the shoulder portion of the belt is centered on your shoulder. The belt should be away from your face and neck, but not falling off' your shoulder. You can be seriously hurt if your shoulder belt is too loose. In a crash, you would move forward too much, which could increase injury. The shoulder belt should fit against your body. 1-44