The real dirty diesel: Coal rollers
Source: The Globe and Mail
... There’s nothing like coal rollers, a group that brings new meaning to the term “dirty diesel.” My first encounter came during a trip through Tennessee in a Toyota Prius. Driving a Prius in coal-roller country is like painting a bull’s-eye on your forehead, since coal rollers refer to diesel exhaust as “Prius repellent.”
While stopped at a traffic light, I found myself behind the kind of pickup truck you tend to see mostly in small towns that have a high concentration of guns and a shallow gene pool: jacked-up suspension, giant wheels and exhaust pipes that resembled the deck guns on the Bismarck. From the rumble, it was clear that it was a diesel.
Moments later, I was engulfed in a thick cloud of black smoke. And by “thick,” I mean the kind of solid smoke wall that naval fleets laid down at the Battle of Jutland to evade enemy fire. My first thought: there had to be something seriously wrong with this truck. I beeped my horn to alert the diesel driver that there was someone behind him. The driver revved his engine and the cloud got even thicker.
... Coal rollers use their exhaust smoke as a political message. It is a symbol of freedom and defiance. They lay down clouds of exhaust on hybrid drivers, cyclists, pedestrians and anyone else who strikes them as a liberal who would restrict their freedom to fill the air with carcinogenic diesel fumes.
... In an interview with Slate magazine, an unnamed manufacturer of smoke-stack kits explained the ethos that underlies coal rolling: “I run into a lot of people that really don’t like Obama at all,” he said. “If he’s into the environment, if he’s into this or that, we’re not. I hear a lot of that. To get a single stack on my truck – that’s my way of giving them the finger. You want clean air and a tiny carbon footprint? Well, screw you.”
Read more: http://www.theglobeandmail.com/globe-drive/adventure/red-line/the-real-dirty-diesel-coal-rollers/article26598563/
= new reply since forum marked as read
How irresponsible of them.
Do they only target Prius drivers or drivers of all hybrid and electric cars? I bet if a Ford Fusion Energy or Tesla P85D were to pass them they wouldn't know the difference. 
Do you live and spend all your time in an urban area? I know plenty of people that own or run ranches, tow horse trailers, etc. Heck, there's a truck in the parking lot outside with some hay in the back.
Earlier this summer. One can draw their own conclusions about the quality of the "gene pool" in Tucson. 
Same here, though. I don't see that many diesel pick-ups. I've never seen this in real life.