The F250 is part of Ford's F-series line of Super Duty trucks. The F250 is a three-quarter ton vehicle that is capable of towing or hauling larger loads than the smaller, half-ton F150. Many F250 trucks come from the factory with towing mirrors that can be extended a few inches to compensate for larger trailer widths. Starting in 2003, a combination turn signal and parking light was installed in the outer edge of the mirror. To replace the bulbs or light lens, the outer mirror cover must be removed first.
Adjust the passenger side mirror using the power control on the driver's door so that it is moved all the way to its outward-most adjustment, creating a gap on the inboard side closest to the side of the truck. Use a flashlight and peer into the mirror housing behind the gap and locate one of the three retaining clips that attach the mirror housing's outer plastic cover. Insert a long flat blade screwdriver into the gap and depress the release tab on the retaining clip.
Adjust the mirror downward to its lowest setting, which should create a gap at the top between the mirror and the housing. Locate the second retaining clip through this gap and release it in the same manner.
Adjust the mirror to its uppermost setting, which should create a gap at the bottom between the mirror and the housing. Locate the third clip through this gap and release it in the same manner. Pull the outer plastic cover from the mirror housing and place it aside.
Locate the mirror light's wiring harness and pull it apart. Pull the light assembly from the housing and remove it from the vehicle. Press in on the two release clips on the light lens to remove it from the light assembly. Push a new lens in position until it snaps into place.
Push the light assembly back into place in the mirror housing. Plug the light's wiring harness back together until it is fully seated. Push the outer plastic mirror housing cover into position until it snaps into place.
Mirror lights on 2008 and newer F250s are held in by a retaining clip. Adjust the mirror so that there is a gap at the bottom outside edge of the mirror. Insert a flat blade screwdriver to release the light retaining clip, which disengages the light from the mirror housing. Once the lens has been replaced, install in the reverse order.