Diesel truck manufacturers are publicly claiming they support a clean, electric future, but are lobbying hard behind the scenes to stall the transition away from polluting engines, the Washington Post reports. Medium- and heavy-duty trucks (like semis) account for nearly a quarter of greenhouse gas pollution from U.S. vehicles, and their exhaust kills thousands of people every year — disproportionately concentrated in low-income communities and communities of color, where highways and warehouse districts create so-called diesel death zones.

Truck makers led a campaign against a new California rule requiring the sale of zero-emissions trucks (now adopted by five other states), and the Truck and Engine Manufacturers Association lobbied for weakening federal safeguards against greenhouse gas and other pollutants. “What we’re seeing from their lobbying is they want to commit to as little as possible,” David Cooke, a senior vehicles analyst with the Union of Concerned Scientists, told the Post. “Promises in press releases don’t actually mean anything. They can say we’re setting a target, we’re spending money, but that doesn’t have to produce results.” (Washington Post $)