Depending on the model year and body type of attachment are different.

Front bumper

-open the hood.

-under the hood take out the caps and Unscrew the screws that secure the top.

-wrenched the wheel to the side.

-wheel arches take out the caps and removed the wheel arches (completely remove is not necessary).

-for wheel arch liners Unscrew one screw and one nut on each side that attach the angles to the wings.

-at the bottom, take out the clips that secure the protection.

-with the assistant pulls  the bumper (don't want to break the wires).

-remove the connectors from the fog lights.

front bumper mounting scheme Cadillac STS

front bumper mounting scheme Cadillac STS

Rear bumper

⇒Tips for removing bumpers and how to avoid breaking anything..⇐

-open the trunk lid.

-in the trunk remove the plastic cover.

-the casing Unscrew the four nuts in the rear.

-Unscrew the screws around the perimeter of the bottom.

-in the wheel wells, Unscrew the screws and take out the rivets that attach the fender liner.

-Unscrew the screws holding the corners of the bumper.

-we release the latch in the wings (pull the corners themselves).

-with the assistant pulls the bumper back.

-(if you have one) remove the connectors of electrical equipment.

rear bumper mounting scheme Cadillac STS

rear bumper mounting scheme Cadillac STS

rear bumper mounting scheme Cadillac STS