In view of changing climatic conditions all over the world GHG reduction initiatives are engaged to reduce the CO2 emissions from mobility and transportation sector. With respect to the large US market, the corresponding legal authorities have defined aggressive and challenging targets for the upcoming time frame. This is especially valid for the highly requested market segment of Light-Duty vehicles, like SUV’S and Pick-Up trucks. In vehicle classes with high Diesel market penetration offers this low CO2 concept a substantial contribution to minimized GHG emissions from the transportation sector. Current Diesel engine portfolio provides an average advantage of 20% reduction in CO2 emissions in contrast to gasoline-powered applications and best-in-class installations achieve already now the stringent CO2 demands of 2020/21 for Europe. For the final customer the fuel consumption behavior in real day usage is much more relevant, where Diesel powered vehicles typically offer even a further attractive attribute, due to the quite flat fuel consumption characteristics over the entire engine map. Therefore, modern fuel efficient Diesel powertrains represent as well a promising technology to support also on the US market for compliance with tight upcoming CAFE standards, at least for heavier applications. The paper in hand provide an overview about core technologies to meet on one hand the ambitious FE figures for SUV’s and Pick-Up trucks in the weight range from 2,5 to 4 tons on the base of a 6-cylinder design with 3,2 ltr. capacity, but also for compliance with the extremely challenging future CARB Tier 2 Bin 2 resp. EPA Tier 3 emission norms. In this context, also the question is analyzed and clarified, if an in-line arrangement for 6-cylinder engines provide a substantial benefit for meeting low CO2 numbers and simultaneously lowest tailpipe emissions versus the very compact and attractive Vee-type layout due to better charging conditions and easier realization of closed-coupled exhaust aftertreatment system positioning. The paper is concluded with an outlook on accompanying transmission and vehicle measures to meet the FC targets.