'Jersey Shore' Ronnie Drops NEW SONG -- Great Message ... Still Douchey

Ronnie from "Jersey Shore" has officially crossed into the music world -- releasing his very own song today ... and the track teaches two valuable lessons ... 1) auto-tune can't fix everything ... and 2) don't drink and drive.

The single's called "How The F%#k We Gettin' Home?!” -- and among the lyrics ... "We don't take it easy / Someone take my keys please / I dont think I'm able to drive."

It still sucks ... but who knows, it might save lives!!!!