- when a husband and wife (or couple) sucks up to, flirts with, or fawns over the local auto mechanic to encourage better customer service, favors or discounts

- any effort utilizing gifts, compliments, or flirting by 2 people to encourage an auto mechanic to provide preferential treatment to them and their cars

the phrase is often combined as a hashtag #greasemonkey3way
My '93 Ford Taurus needed a new transmission. Luckily my wife and I gave the mechanic a greasemonkey 3 way and he was willing to stay late and get it done before our trip to Chicago the next day. He rotated the tires for free, too!
by The Poobah October 24, 2013
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