Chevrolet 2007 HH7 Owner's Manual page 16

To raise the seatback to an upright position, do
the following:
1. Pull up on one of the two levers located on
the rear of the seat near the bottom of either
side of the seat.
2. Push the seatback up until it is in a locked
position.
16
CAUTION:
{
If the seatback is not locked, it could
move forward in a sudden stop or crash.
That could cause injury to the person
sitting there. Always push and pull on the
seatback to be sure it is locked.
3. Push and pull on the seatback to make sure it
is locked.