Depending on the year of manufacture, the mounting points may differ.
Front bumper
-open the hood.
-under the hood, pull out the pistons that attach the upper part.
-from the bottom side, we Unscrew the screws and pull out the pistons that attach the lower part.
-turn the wheels out of the way.
-in the wheel arches, Unscrew the screws and release the slats (front part).
-we take the wing flaps aside and Unscrew two screws and one nut on each side, which attach the corners to the wings.
-with an assistant, we pull the bumper forward (look for the wires).
-disconnect the electrical equipment connectors (if any).
Rear bumper
-open the trunk lid.
-in the opening of the trunk, we pull out the pistons that attach the upper part.
-release the fasteners from the bottom side.
-in the wheel arches, we Unscrew the screws and pull out the pistons that attach the undercarriage.
-behind the wing slats, we release the fasteners of the bumper corners to the wing.
-with the assistant carefully pull the bumper back (look for the wires).
-snap together the connectors of the sensors.
How to remove the front and rear bumper Pontiac Montana (1997-2004)