Lubricants supplied by tool manufacturers are usually very overpriced and they are seldom anything special. I have a Red Max string trimmer. They are high end and used by many landscapers. I dug out my owners manual to refresh my memory and see what they called for. Happily, they do not call for some RedMax grease at a gazillion dollars a tube.. They say to use a multi purpose lithium base grease. I am assuming there is a grease fitting on your Milwaukee so you will want a grease cartridge. I did a quick search and Valvoline Cerulean seems to fill the bill. It is carried by Auto Zone and Advance so it should be easy to come by and it is a quarter of the price of the Milwaukee stuff. Many of the auto greases are lithium based. If you work on your car, you might even have some on hand.
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