When stupid-ass white trash people turn the injection pump up on rickety-ass broken down 12V Cummins-powered Dodges and subsequently install 5" smokestacks in the bed of said Dodge. Then said WT decides to post youtube videos of their truck blanketing neighborhoods with black diesel soot.

Regardless of engine technology progressing to the point of nearly eliminating black smoke and producing nearly double the power of modded mechanically-injected diesel engine in stock form, a "Coal Rollin'" owner will respond with a not-so-clever response of "I'd rather be Cummin than Strokin." Referring to his belief that his Cummins engine is better than International's Powerstroke engine series found in Ford trucks. Because Isuzu's Duramax engien found in GM-branded trucks cannot be directly correlated to any phallic self-gratification, they are typically ignored. See Below for why

This particular stereotype is the progression of the IROC Camaro owner in the 1990s and the lowered Civic Hatchback owner in the early 2000s. They can be identified by their love of Nickelback, lack of personal hygiene, closeted homosexuality and morbid obesity. A majority of these owners reside in Florida, this species also can be found in eastern Texas, Alabama, Georgia, and California's central valley.
"Check 'er out fellas I was rollin' coal through that there intersection antagonizing queers. Y'all want to get naked and jump in a mudhole together?"
by Fordfascist May 14, 2010
When your in a diesel truck and have the injection pump turned way up and you mash the throttle to overfuel the motor, thus making a cloud of black smoke until your turbocharger spools up. Best done in a 12 valve Cummins Turbo Diesel powered Dodge Ram pickup, as they are by far the best sounding and most reliable pickups built, plus, the pump is tuned with a screwdriver and allen wrench on the P7100 equipped engines. Also best done with a high dollar car behind you, preferably driven by an attractive female, homosexual male, city slicker, or tree-hugger.
"Hahaha dude did you see me rollin' coal on that stupidass tree-hugger in the hybrid Honda?" "Yeah dude, he couldn't see 20 feet in front of him"
by Diesel Dave April 25, 2007
Is what a tailgater, jack rabbit that charges up behind you and stays there... or any other vehicle bigger than YOU (my A-to-B is an 80s VW Rabbit diesel hatchback) when they refuse to back off when you want to slow down to make a right-hand turn when there is no turn lane...eats when you want to tell them very pointedly to either PASS or GET OFF MY ASS!

To accomplish this end in a vehicle with a manual transmission...just drop the clutch and punch the throttle. In an automatic...floor it.
"What the hell? You a near sighted hemorrhoid with broken brakes? I need to turn damn it! I signaled a half mile ago! EAT THIS! "
drops clutch & gooses throttle
semi in rear view mirror disappears behind a cloud of rollin' coal
by RuralTowner March 31, 2017
rollin coal is a redneck high school term used for idiots who thin its cool to over-heat there turbo and redneck rig there diesel( cummins "smoke screw" , smoke switch) to blow the most black smoke from there exhaust as they possibly can. there is no point to roll said coal if you want smoke do it right and do injectors intake turbo and chip and smoke will come as a by product but keep it off the road. Those coal rollers are why diesel has so many emmisions restrictions.
"hey you see that idiot rollin coal all over that guy on a motorcycle?" " yeah look at that cop pullin him over"
by strokethis January 10, 2012
To over-fuel a diesel motor to the point that thick black smoke comes rolling out of the exhaust. Usually associated with modified or "BOMBED" diesels it shows you can actually make some power.
Why does your truck smoke?

Im rollin coal!
by muddyxj July 30, 2008
The act of passing a thick, noxious gas out of your your ass while passing through large crowed areas. Bonus points if it is loud and has a clingy consistency, as you want people to know that your are the villain of this dastardly deed. Not to be confused with carpet bombing or crop dusting whereas the pilots try to remain anonymous while dumping their payloads in crowded areas.
I was with my Uncle and he was Rollin Coal all over them pansies waiting in line at the blood donation center.
by rustintime July 10, 2014