Mercedes-Benz M156 engine
The M156 is the first V8 automobile engine designed autonomously by Mercedes-Benz subsidiary Mercedes-AMG, as previous AMG engines have always been based on original Mercedes engines. The engine was designed to be a naturally aspirated racing unit, and will also be used in a number of high-performance "AMG"-badged Mercedes-Benz models.
The M156 displaces 6,208 cc (6.208 L; 378.8 cu in) and shares very little with other Mercedes-Benz engine families like the M155. The bore spacing, block design, and other features are unique to the AMG engine.
Although this engine displaces 6.208 liters, the engine is marketed as the "6.3" to commemorate the famed Mercedes-Benz M100 engine, Mercedes' first production V8 which initially displaced 6.3L.
The engine uses a 102.2 mm (4.02 in) bore and 94.6 mm (3.72 in) stroke. Output is 375 kW (503 hp) at 6800 rpm with 630 N·m (464.7 lb·ft) of torque at 5200 rpm.
The engine, however, has been uprated to produce 518 hp (386 kW) (and 465 lb·ft (630 N·m) of torque) in the late 2007 S 63, E 63, SL 63, CLS 63 & CL 63 models.
Mercedes has (arguably) claimed it is the world's most powerful naturally aspirated V8 engine.
- 2006 E 63 AMG
- 2006 ML 63 AMG
- 2006 R 63 AMG
- 2006 S 63 AMG
- 2006 CL 63 AMG
- 2007 CLK 63 AMG
- 2007 CLS 63 AMG
- 2008 C 63 AMG
- 2008 SL 63 AMG
In 2011, a class action lawsuit was filed in United States District Court in New Jersey against Daimler AG, Mercedes-Benz, Mercedes-AMG for alleged defects in the M156 engine contained in AMG vehicles built in 2007-2011 model years leading to premature wear. The plaintiff claimed the combination of cast nodular iron camshafts and 9310 grade steel valve lifters contributed to the premature wear, but the defendants had known about the defect since 2007.
The lawsuit lasted approximately 14-months. In November, 2012, litigation came to a halt when the New Jersey District Court dismissed the plaintiffs’ first amended complaint for lack of standing. The plaintiffs were given the opportunity to further amend their complaint to show that they had standing to sue, but plaintiffs made no further filings with the Court. On January 7, 2013, the Court signed an order closing the case. 
It is a version used in Mercedes-Benz SLS AMG. Compared to the standard AMG engine, the SLS's engine includes an all-new intake system, reworked valve train and camshafts, the use of flow-optimised tubular steel headers and dethrottling of the exhaust system. The engine also utilizes a dry-sump lubrication system to lower the center of gravity of the car.
|Engine code||Years||Displacement (Bore x Stroke)||Compression (:1)||Power @rpm||Torque @rpm||Redline (rpm)|
|M 159||2010-||6,208 cc (6.208 L; 378.8 cu in) (102.2 × 94.6 mm (4.02 × 3.72 in))||11.3||571 PS (420 kW; 563 hp) @6800||650 N·m (479 lb·ft) @4750||7200|
|M 159||2012-||6,208 cc (6.208 L; 378.8 cu in) (102.2 × 94.6 mm (4.02 × 3.72 in))||11.3||591 PS (435 kW; 583 hp) @6800||650 N·m (479 lb·ft) @4750||7200?|
|M 159||2013-||6,208 cc (6.208 L; 378.8 cu in) (102.2 × 94.6 mm (4.02 × 3.72 in))||11.3||631 PS (464 kW; 622 hp) @7400||635 N·m (468 lb·ft) @5000||8000|
- 300 SEL 6.8 AMG
- Class action lawsuit to be filed against Mercedes alleges AMG V8 defects
- Regar, Jacob. "Update: Mercedes Benz AMG Class Action for the M156 V8 Engine". jacobregarlaw.com/Blog. Jacob Regar Law. Retrieved 16 February 2013.
- Mercedes-Benz SLS AMG: fascination and high tech: The new 'Gullwing' from Mercedes-Benz
- "New AMG 6.3 Liter V8 Engine -In Detail". GermanCarFans. Retrieved January 16, 2006.