Mercedes-Benz developed the BlueTEC technology that focuses particularly on nitrogen oxides in order to reduce the emissions of diesel vehicles. The tech involves injecting a non-toxic aqueous carbamide solution called "AdBlueÓ" into the exhaust gas flow that then releases ammonia. In the downstream SCRcatalyst system the ammonia then converts up to 80 per cent of the nitrogen oxides into the harmless products nitrogen and water.
According to the German automaker, the GL350 BlueTEC 4MATIC, ML350 BlueTEC 4MATIC and R350 BlueTEC 4MATIC already fulfill the emissions limits of the EU 6 standard, which won't go into effect until 2014.
As for the BlueTEC models' combined fuel consumption, the ML-Class and R-Class variants both return an average of 8.7 lt/100km (27mpg US) while the larger and heavier GL-Class has been rated at 9.0lt / 100km (26.1mpg US).