WD40 or light machine oil. Or I got some stuff called Kluber structovis that sprays on like WD40 then evaporates off the propellant and becomes a light grease. It works well too.

 

Every year we wash and lube the cable,also spool out then spool in to check for damage

 

My winch manufacturer recommends using "penetrating oil" on the steel cable. Before using the winch they recommend unspooling and re-spooling under a 500# or so load (such as pulling the Jeep) to pre-stretch the cable. At that time, I treated the cable with Liquid Wrench lubricating oil which is similar to WD-40. CRC Power Lube would also work well.

 

penetrating what?! ha jk ive used many different kinds and all seem to work ok.