1996 GMC Sonoma Owner's Manual - Page 13

Seatback Latches To return the seatback to the upright position. push the seatback a l l the way back until the latch catches. if the seatback was reclined before being folded forward, it will return to the reclined position. forward, lift the latch and push the seat forward. If the seatback isn't locked, it could move forward in a sudden stop or crash. That could cause injury to the person sitting there. Always press rearward on the seatback to be sure it is locked. 1-5