Every 3000 miles or each 3 months, couples of drops of light or lock lubricant should on the hinges and latch assembly of the doors, the 
Hood as well as the tailgate or the lift gate. Also, the door latch strikers should be greased with thin layer of grease to reduce signs of wears and to enhance its operation. One should also apply spray on graphite lubricant on the door and lift gate locks.