1998 Chevrolet Blazer Owner's Manual - Page 25

On two-door models withan inside mounted spare tire, the driver's side rear seat head restraint must be lifted and held upright as the seatback is raised. Otherwise, the head restraint will hit the spare tire and prevent the seatback from properly latching. Push and pull onthe head restraints to check that they have locked in the upright position. If they haven't, have them fixed immediately. The rear seat headrestraints are adjustable. Push the button located underthe head restraint to raise or lower it. Slide the head restraint up or down so that the top of the head restraint is closest to the top of your ears. After releasing the button, push and pullon the head restraint to make sure it's locked in place. To return the headrestraints to the upright position, reach behind the seats and pull the headrestraint up until it locks into position.