For Benz W221 S 500 L 4MATIC M273.968 7A/MT gasoline engine
The M273.968 5.5L engine featured in the Mercedes-Benz S500 is a naturally aspirated 90° V8 engine (with a displacement of 5,461 cc), primarily utilized in the S500/S550/CL500 models of the W221/C216 series (model years 2007–2011). This engine produces an output of 382–387 horsepower (282–285 kW) and 391 lb-ft (530 N-m) of torque, and features an all-aluminum construction, a DOHC (Dual Overhead Camshaft) design, and four valves per cylinder.
Description
Key Engine Specifications (M273.968 / M273 E55):
Engine Type: V8, Naturally Aspirated (90-degree V-angle).
Displacement: 5.5 Liters (5,461 cc).
Bore / Stroke: 97 mm × 82.1 mm (3.82 in × 3.23 in).
Max Power: Approx. 382 hp (285 kW) at 6000 rpm.
Max Torque: 391 lb-ft (530 N·m) at 2700–5000 rpm.
Compression Ratio: 10.7:1.
Fuel System: Gasoline Direct Injection.
Valve Train: DOHC (Dual Overhead Camshafts), 4 valves per cylinder.
Application Details:
Applicable Models: Commonly found on 2007–2011 CL500/CL550 (C216) and related S-Class models.
Transmission: Typically paired with the 7G-Tronic 7-speed automatic transmission.








