There is a new end for a grease gun end out that locks onto the zerk. this is not a good idea have heard from several that it will blow out the rubber boot worse if used with a rechargeable grease gun. Take a few extra minutes and replace the zerk. Next time I get my oil changed I will ask about the use of both of these. On occasion I do look under and make sure my vehicle has been greased. I know my Bonneville was had a squeak and it went away. Just a hint go around and lube the door hood and trunk hinges also the door and trunk locks. Give the weather strip a shot of WD-40 this is one good use for it. . A good time to do this before it gets cold.