The Montana nameplate started as a trim level for Pontiac's Trans Sport van in 1997 and 1998, then became a model in its own right in 1999. The 2005 Montana had the option of a rear cargo convenience center and stowable seat. The seat was a third-row bench that increased passenger capacity, making the Montana one of the few minivans that could provide seating for eight.
Clear all items from the convenience center. All the way at the rear of the minivan, find the convenience center knob down low, below the handle. Turn the knob counterclockwise until it is loose, then lift the knob up, lifting up the convenience center. Pull the center toward you and remove it from the Montana.
Pull up on the seatback lever to release it, then find and pull the strap on the right side of the seat so you can pull the seatback up and secure it in the upright position.
Push up the release levers behind the seat to release the latches from the floor. Let go of the lease levers and grasp the crossbar at the bottom of the seat. Tilt the seat slightly toward the rear of the minivan, then give it a heave to pull it out.
To install the seat, angle the seat so the front hooks clear the floor pins, then insert the front hooks of the seat onto the forward floor wells of the third row to engage the pins. Push the rear of the seat down so the rear hooks engage the rear floor pins. Tug up on the seat, and push and pull it back and forth to make sure it is locked into position.
With the convenience center closed, lift it and place it in the back of the minivan. Lift the tray sill to the upright position, then slide the convenience center into position, aligning it so that the bottom rear forks engage the seat anchors.
Push down on the center front of the convenience center so the middle aligns on the sill mounting bracket, then turn the knob clockwise until it is tight. Give the convenience center a tug to make sure it is locked in place.
