SoylentNews

upstart writes in with an IRC submission:

Aftermarket truck mods pollute as much as 9 million extra pickups:

As automotive subcultures go, intentionally modifying your truck's diesel engine to make extra pollution is one of the more antisocial ones out there. According to the US Environmental Protection Agency, diesel trucks with disabled emissions controls are far more widespread than you might think and emit more pollution than the diesel engines that got Volkswagen such hefty fines.

In 2016, Volkswagen agreed to a pair of court settlements totaling nearly $16 billion after it was caught selling diesel vehicles fitted with emissions defeat devices. In total, the VW scandal affected more than half a million cars and SUVs sold in the US, which produced up to 40 times the legal limit of nitrogen oxides (NOx) when in daily operation.

According to the EPA's Air Enforcement Division, the use of aftermarket emissions defeat devices by diesel truck owners rivals that problem. In a report first obtained by The New York Times, it estimates that 550,000 medium trucks have had their emissions systems tampered with over the last decade—fully 15 percent of the diesel trucks on US roads.

[...] They sure are dirty. The EPA report says that 570,000 tons of excess NOx and 5,000 tons of excess diesel particulates are the result over the course of these trucks' lifetimes. Or to put it another way, "due to their severe excess NOx emissions, these trucks have an air quality impact equivalent to adding more than 9 million additional (compliant, non-tampered) diesel pickup trucks to our roads."

Original Submission