Depending on the year of manufacture, the attachment points may differ.
Front bumper
-open the hood.
-take out the four clips (inserted from top to bottom) that secure the upper part of the bumper.
-in the lower grille take out two pistons (inserted from the bottom up).
-at the bottom of the bumper, Unscrew the six screws (spun up).
-turn the wheels to the side.
-in the wheel arches release the fender liner.
-unscrew two screws on each side (spun up) that secure the corners of the bumper to the wings.
-with an assistant, pull the bumper forward (look for the wires).
-disconnect electrical connectors (if any).
Rear bumper
-open the trunk lid.
-in the trunk, remove the rear and side trim.
-from the trunk, Unscrew the four nuts in the rear panel.
-in the inner part of the wings, Unscrew two screws and two nuts on each side.
-at the bottom of the bumper take out four pistons (inserted from the bottom up).
-in the wheel arches, we release the fender liner (rear).
-unscrew one screw on each side (spun up) that attach the corners of the bumper to the wings.
-with an assistant, pull the bumper back (look for the wires).
-disconnect electrical connectors (if any).
How to remove the front and rear bumper Toyota Avalon (2005-2012)
How to remove the front and rear bumper Toyota Avalon (2013-2018)
How to remove the front and rear bumper Toyota Avalon (2019+)