All of our polymer lead nuts are internally lubricated, so lubrication is not necessary. However, lubrication is recommended to optimize efficiency and life.  Lubrication reduces friction and wear between the nut and screw. The type of lubrication and maintenance schedule will depend upon the operating environment. Care should be taken in dirty environments to use a lubrication that will not become contaminated and form an abrasive slurry or thicken. Bronze lead nuts and Ball screws must be lubricated to operate properly and achieve rated life.