The term E-4 Mafia refers to the network of SrAs, SPCs (and some CPLs) who do most of the things that actually get done in the Army and Air Force. Not all E-4s are in the Mafia, but by the time you get to E-4, they've probably done something for you, and by the time you finish being an E-4, you'll probably have done something for them, too.

They are the support personnel in positions where they know what is going on, know what is going to happen, and "know a guy" who can get things done that you need done.

Need a last minute appointment at the Dental Clinic? The E-4 Mafia has an agent in place that can make that happen for you.
Have a pay problem that needs resolving? The E-4 Mafia has a finance clerk that really knows how to get things fixed.

Need someone to take your CQ runner shift next weekend? The e-4 Mafia know a guy who's willing to do it for $100.
Have a new troop who's ate up like a soup sandwich? The E-4 Mafia know a guy who can train him.

But there's a dark side as well.
Have a supervisor who is a real PITA? Your E-4 Mafia can make his life into a little slice of hell. Appointments get rescheduled, supplies are not there for him, his POV always comes up for the "random" search at the gate, his pay problem paperwork stays at the bottom of the in-pile for two extra weeks, his dental appointment is with "the butcher" instead of the good one, he's always the last to get the word about anything in the unit, etc.
I was supposed to be PCSing in June, but my assignment got delayed, I couldn't get a resolution through normal channels, then the E4-Mafia got involved, a buddy called a friend at HQ, sorted things out, and my orders came through in two days.
by WTF-O August 8, 2017
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The E-4 Mafia is the unofficial "gang" of the Specialist rank in the U.S. Army. Notorious for knowing more than the E-5 Sergeants and normally too much for their own good. Squad leaders are usually very pissed off when "secret" plans reach the E-4 Mafia before THEY even hear about it. Usually their intelligence comes from untrustworthy sources, but sometimes they get lucky.
GOD DAMN THAT E4-MAFIA, HOW MANY TIMES DO I HAVE TO TELL YOU NOT TO LISTEN TO THEM, PRIVATE!!
by Mikeymoped January 1, 2011
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