I would keep them clean - remove all salt and other dirt and grime with warm water (out of a garden spray nozzle, no pressure washing), clean them with a distilled solution of simple green, and then rinse again with warm water. Clean them in the extended position. Make this part of your routine with the truck. Either air dry or use a small leaf blower to blow them dry. If the owners manual says to grease them, do so, in the manner and with the particular Mopar product specified. If there is no advice on this in the manual, I would still probably still lubricate any visible hinges with the same type of grease specified for door hinges.