Daimler announced on 13 March 2008 that its Mercedes-Benz brand had become the first auto manufacturer to receive US Tier 2 Bin 5 (50 state) certification for a diesel passenger car. The certified vehicles are the GL320, ML320 and R320 and comprise the second generation of BlueTec vehicles.

The first generation of Mercedes BlueTec range uses a non-urea SCR system downstream of a NOx storage converter, oxycat and DPF. This arrangement, used in the E300 and E320 models does not meet Tier 2 Bin 5 requirements and cannot be sold in states that have followed California's early adoption of Bin 5 legislation. The GL320, ML320 and R320 will use urea SCR with an oxycat and DPF.