Below are the procedures to fix the bumpers. Arrows indicate the location of screws, rivets and latches.

Front bumper

front bumper mounting scheme Buick LaCrosse (2004-2008)

front bumper mounting scheme Buick LaCrosse (2004-2008)

Rear bumper

rear bumper mounting scheme Buick LaCrosse (2004-2008)

 

How to remove front and rear bumper Buick LaCrosse (2009-2016)