Q: How do you remove and install the front and rear bumpers on Lincoln Navigator?
A: Begin by applying the parking brake, raising the vehicle, and securely supporting it on jackstands. Disconnect the negative battery cable followed by the positive battery cable, then wait two minutes before proceeding. For the front bumper on Pick-up and Expedition models, work under the vehicle to disconnect the fog light electrical connections if equipped, and release the pushpins securing the lower air deflector panel for access to the fog light connectors. From the backside of the bumper, remove the retaining bolts securing the bumper brackets to each frame rail, then remove the bumper. For installation, reverse the removal steps. On Navigator models, detach the bolts and plastic clips securing the plastic air deflector from underneath the vehicle. In the front wheel opening, detach the retaining nuts securing the bumper cover to the fender, noting that later models have four bolts on each side. Remove the retaining bolts at the lower front edge of the wheel opening, disengage the release tabs in the grille opening, and remove the bumper cover. Disconnect any electrical connections that may interfere with removal, then remove the retaining bolts securing the bumper brackets to each frame rail and take off the bumper. For the rear bumper on Pick-up and Expedition models, remove the license plate light bulbs from the rear bumper, and for 2005 and later Expedition/Navigator models, disconnect the backup light connectors. Remove the retaining bolts securing the bumper brackets to each frame rail, then take off the bumper, reversing the steps for installation. On Navigator models, detach the plastic clips and screws securing the inner splash shield from underneath the vehicle, then remove the nuts and bolts securing the bumper cover to the rear quarter panels. Open the liftgate to remove the plastic clips securing the upper edge of the bumper cover, and for 2003 through 2006 Expedition/Navigator models, remove the lower rear floor trim panel to access the fasteners. Lift upward and pull outward to remove the bumper cover, then remove the retaining bolts securing the bumper brackets to each frame rail before taking off the bumper, with installation being the reverse of removal.