2003 GMC Sonoma Owner's Manual - Page 34

Rear Seat Passengers (Crew Cab) I .. It's very important for rear seat passengers to buckle up! Accident statistics show that unbelted people in the rear seat are hurt more often in crashes than those who are wearing safety belts. To make it shorter, pull the belt, as shown until it is snug. Buckle and position it the same way as the lap part of the driver's safety belt. See Driver Position on page 1-17. Make sure the release button on the buckle is positioned so you would be able to unbuckle the safety belt quickly if you ever had to. To unlatch the belt, just push the button on the buckle. Don't use a child restraint on this seat. It won't work properly. 1-27