When an E-4 calls me "hey" or "hey man" knowing that I am an officer, should I bother to correct him?

Lt. J.R., during my full career i have never stepped out of order when around officers even after the base nco/officer clubs first combined, during off duty parties or any gatherings. It was Sir or by rank. i would say something to that SPC.

Sir,
Yes, you correct the issue on the spot. You are doing him a disservice by allowing the behavior to continue.

While working with subordinates they must respect the rank and address accordingly. Outside of work? There is no such thing as outside of work in the military. In uniform or out of uniform, respect the rank and address accordingly. Period!

what the hell kind of question is that? If you don't know the answer to that, resign, just resign...

Just like them salute you with the left hand, you should correct it immediately

the regs tell you are a soldier 24/7 so this spec-4 or e-4 should be addressing by sir every time he sees you just check your UCMJ manual

First off as being an officer and O3 in the Army, you should never let any enlisted member call you “hey man” period. If you do then you should ask yourself do have the right to wear those Captains bars. The military has gotten away from the simple fact that there is rank and privileges and we are to give them regardless of the time and place. Doesn’t mean we have to like the person but the rank and privileges have not gone away. The military is getting sloppy and this type of question should never be asked. And if any good senior no saw it should have taken that E-4 out and…. Well let’s just say it’s not the old military anymore sadly.

Of course you should. If you don't enforce discipline over the smaller things how can you enforce it on the larger things?

My humble opinion; not only is the person in need of training but as an NCO, he's potentially setting the example for anyone under him.

Not about rank, it’s respect which is leadership. Especially within the company level it becomes more about friendship and family where I have learned it’s about knowledge. When someone is around or a NCO or Officer from another company or not familiar with then it’s a must to address by rank, respect and professionalism. Off base, different story. After 10-12hrs days, down range, deployments and home no one needs that BS. What bothers me more is disrespecting the uniform. Can’t stand when see not wearing a hat, shirt off/unbuttoned, laces untied etc… should look professional at all times. See this more often with the reserves. Too much effort is put in throughout the year to play the lifer game yes Sargent, no Sargent off base. Usually the “nod” is sufficient..