The doors on vehicles are mounted using a hinge and hinge pin system. Accidents, or the wear and tear of normal usage over time can weaken the components of the system and damage the parts. If the hinges or door pin crack, or parts break off, your door can sag out of alignment and present problems opening and closing. If this happens, you will need to replace the broken part.
Open the door and examine the bolts holding the hinge to the inside of the door and the hinge to the door frame for damage. If any of the bolts are loose, tighten them and see if this brings the door in line.
Inspect the hinge for damage. In most cases, the hinge on either the door itself or the inside of the door frame will have a crack running through it. This allows the weight of the door to pull against the hinge and stretch the metal; as a result, the door will begin to sag and becomes more out of alignment as time passes.
Examine the hinge pin. See if a part of it is missing or damaged.
Remove the small restraining ring from the bottom of the hinge pin using a flat head screwdriver. Place the blade of the screwdriver under the ring and apply force to it; it should loosen and pop off.
Have someone support the door upwards to remove pressure from the hinges. Insert the blade of the screwdriver underneath the head of the hinge pin and use it to pry the pin upwards. Work the hinge pin up and out of the hinges. Carefully place the door on supports; do not move it too far from the vehicle or pull on it, as this will damage the wires running into it.
Align the hinges and insert a new hinge pin if the hinge pin is the damaged part. Press the new retaining ring on the pin. If the pin is not damaged, see Step 7.
Remove the hinges from the door and door frame using a socket and ratchet.
Attach the new hinges to the door and door frame with the bolts you removed. Make sure to tighten the bolts all the way. If they are left loose, they will work further out and the door will sag again.
Have the other person hold the door in place so that the hinges are aligned. Insert the hinge pin through the new hinges and snap the retaining ring in place on the bottom of the pin.
