Another trick from the automobile industry?
Despite having the same exhaust system, some diesel cars emit more than twice nitrogen oxide than a trailer of 18 tons. And besides, it is legal. This is the case of Mercedes “C 220 CDI” with a nitrogen oxide emission of 643 mg/km compared to 250 mg/km from the cargo truck “Actros 1848”.
The reason is that to get the truck’s permission of use, a test under real conditions is carried out. By contrast, for the automobile the permission is gotten only by fulfilling theoretical values obtained from the laboratory.