1999 GMC Sonoma Owner's Manual - Page 8

yellowblue Seats and Seat Controls This section tells you about the seats -- how to adjust them, and fold them up and down. Manual Front Seat CAUTION: You can lose control of the vehicle if you try to adjust a manual driver's seat while the vehicle is moving. The sudden movement could startle and confuse you, or make you push a pedal when you don't want to. Adjust the driver's seat only when the vehicle is not moving. Pull up on the lever under the front of the manual seat to unlock it. Slide the seat to where you want it. Then release the lever and try to move the seat with your body to make sure the seat is locked into place. 1-2