The Mercedes-Benz M278 engine is a powerful, twin-turbocharged V8 engine, but it's important to note that it's not typically branded or used in AMG models. Instead, AMG models usually feature engines specifically developed by AMG, such as the M157, which is a higher-performance variant of the M278. However, the M278 engine itself is found in a range of high-performance Mercedes-Benz vehicles that offer substantial power and luxury, even if they are not AMG-branded. The M278 engine, known for its robust performance and efficiency, is equipped in various non-AMG Mercedes-Benz models across the United States and Canadian markets. Below are the years, models, and chassis codes of Mercedes-Benz vehicles equipped with the M278 engine: Mercedes-Benz S550 (W221): 2012-2013 Mercedes-Benz S550 4MATIC (W222): 2014-2017 Mercedes-Benz CLS550 (W218): 2012-2018 Mercedes-Benz E550 (W212): 2012-2016 Mercedes-Benz GL450/GL550 (X166): 2013-2016 Mercedes-Benz ML550 (W166): 2012-2014 Mercedes-Benz SL550 (R231): 2013-2018 Mercedes-Benz G550 (W463): Specific years vary, generally around 2013-2018 These vehicles, while not under the AMG marque, are highly regarded for their luxury, comfort, and notably enhanced performance thanks to the M278 engine. They provide a blend of everyday usability with the excitement of a powerful V8 engine, appealing to a wide range of drivers who seek Mercedes-Benz's renowned engineering and performance without venturing into AMG territory. For those looking to enhance the performance of their M278-equipped vehicle further, options like M278 ECU Tuning by professional tuners can unlock additional power and efficiency from the engine, providing an even more spirited driving experience in models such as the E550 W212, CLS550 W218, S550 W222, S550 W221, GL 450 GL550 X166, and ML550 W166.