Every 3000 or 300,000 miles (whichever happens first) or once every three months, oil or lock lubricant should be applied as a few drops to the hinges and latch assemblies on the doors,
Hood, and trunk (or liftgate). Also, door latch strikers should be lubricated with a very thin coat of grease to minimize wear, so door latch strikers move freely. Spray the door and trunk (or liftgate) locks with spray on graphite lubricant.