2004 GMC Yukon Owner's Manual - Page 13

Head Restraints {CAUTION: Sitting in a reclined position when your vehicle is in motion can be dangerous. Even if you buckle up, your safety belts can't do their job when you're reclined like this. The shoulder belt can't do its job. In a crash, you could go into it, receiving neck or other injuries. The lap belt can't do its job either. In a crash the belt could go up over your abdomen. The belt forces would be there, not at your pelvic bones. This could cause serious internal injuries. For proper protection when the vehicle is in motion, have the seatback upright. Then sit well back in the seat and wear your safety belt properly. Adjust your head restraint so that the top of the restraint is closest to the top of your head. This position reduces the chance of a neck injury in a crash. To raise the head restraint pull up on the head restraint. On some models the head restraints tilt forward and rearward also. The rear seat head restraints in your vehicle may be adjustable. They work the same as the front seat head restraints, except they do not tilt forward and rearward. 1-7