The Mercedes-Benz M 157.981 is a 5,980 cc, twin-turbocharged V8 petrol engine produced between 2013 and 2017. It served as the high-performance powerplant for the S-Class (W222) and CLS-Class (C218) AMG variants, delivering exceptional power and refinement. Featuring a 90° V8 configuration, DOHC, four valves per cylinder, and twin-scroll turbocharging, it produced 430 kW (585 PS) and 900 Nm of torque, enabling 0–100 km/h acceleration in under 4 seconds.
Fitted to the S 63 AMG (W222) and CLS 63 AMG (C218), the M 157.981 was engineered for dynamic performance and grand touring capability. Its design emphasizes rapid turbo response, linear power delivery, and low-end torque, ideal for high-speed motoring and spirited driving. Emissions compliance is achieved through close-coupled catalytic converters and precise lambda control, meeting Euro 6 standards across its production run, with all models certified under UK VCA Type Approval #VCA/EMS/5683.
One documented concern is premature wear of the high-pressure fuel pump (HPFP), highlighted in Mercedes-Benz Service Information Bulletin 07.0127/14. This issue, affecting select 2013–2015 production units, stemmed from elevated thermal loads on the pump’s internal components. From 2016, revised materials and cooling protocols were implemented to enhance durability.
All production years (2013–2017) meet Euro 6 standards (VCA UK Type Approval #VCA/EMS/5683).
The Mercedes-Benz M 157.981 is a 5,980 cc twin-turbocharged V8 petrol engine engineered for high-performance luxury sedans and coupes (2013–2017). It combines a 90° V8 layout with twin-scroll turbochargers and direct injection to deliver aggressive power delivery and daily drivability. Designed to meet Euro 6 emissions standards, it balances track-ready performance with road legality and refinement.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 5,980 cc | |
| Fuel type | Petrol (Unleaded, 98 RON min, 100 RON recommended) | |
| Configuration | 90° V8, DOHC, 32-valve | |
| Aspiration | Twin-turbocharged (hot-V layout) | |
| Bore × stroke | 83.0 mm × 92.0 mm | |
| Power output | 430 kW (585 PS) @ 5,500 rpm | |
| Torque | 900 Nm @ 2,250–3,750 rpm | |
| Fuel system | Direct fuel injection (up to 200 bar) | |
| Emissions standard | Euro 6 | |
| Compression ratio | 10.0:1 | |
| Cooling system | Water-cooled (dual-circuit) | |
| Turbocharger | Twin twin-scroll turbo (hot-V, exhaust manifold-integrated) | |
| Timing system | Chain (front-mounted, reinforced) | |
| Oil type | 0W-40 or 5W-40 (MB 229.52) | |
| Dry weight | 226 kg |
The twin-turbo V8 delivers race-derived performance but demands strict adherence to 15,000 km oil change intervals using MB 229.52-specified oil to ensure longevity of the high-pressure fuel pump and turbochargers. 0W-40 or 5W-40 viscosity is critical due to high thermal loads and bearing speeds. Extended high-RPM operation without cooldown increases turbo and HPFP stress. Fuel quality (minimum 98 RON, 100 RON recommended) is essential to prevent knock and protect the high-compression design. Post-2016 engines feature upgraded HPFP components per Mercedes-Benz SIB 07.0127/14; pre-2016 units should be inspected under high-load conditions. Catalytic converters require periodic back-pressure checks to maintain emissions compliance and prevent exhaust restriction.
Oil Specs: Requires MB 229.52 specification (Mercedes-Benz SIB 07.0127/14). Compatible with ACEA C5 standards.
Emissions: Euro 6 certification applies to all models (2013–2017) (VCA Type Approval #VCA/EMS/5683).
Power Ratings: Measured under ISO 1585 standards. 430 kW output requires 100 RON fuel (Mercedes-Benz TIS Doc. 27-7006).
Mercedes-Benz Technical Information System (TIS): Docs 27-7006, 07.70-P-1006-01, SIB 07.0127/14
VCA Type Approval Database (VCA/EMS/5683)
ISO 1585: Road vehicles — Engine test code — Net power
The Mercedes-Benz M 157.981 was used across Mercedes-Benz's W222/C218 platforms with longitudinal mounting and reserved for AMG 63 variants. This engine received platform-specific adaptations-higher boost in the W222 S 63 S and revised intake in the C218 CLS 63 AMG-and from 2018 the next-generation AMG 63 models adopted the M 177, creating interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped vertically on the left-side engine block near the transmission bellhousing (Mercedes-Benz TIS 27-7006). The 8th VIN digit indicates engine family ('M' for AMG petrol series). All units have black cam covers with red AMG lettering. Critical differentiation from M 177: M 157.981 has a hot-V turbocharger with exhaust manifold integrated into the cylinder head, while M 177 uses a side-mounted twin-scroll setup. Service parts require production date verification - high-pressure fuel pumps for engines before 07/2016 are incompatible with later units due to internal redesign (Mercedes-Benz SIB 07.0127/14).
The M 157.981's primary reliability risk is high-pressure fuel pump wear on early builds, with elevated incidence in vehicles used for track or aggressive driving. Internal Mercedes-Benz quality reports from 2016 noted a notable share of pre-2016 engines requiring HPFP replacement before 80,000 km, while VCA records show a small but significant number of emissions-related MOT failures linked to lambda sensor faults from rich-running conditions. Extended high-RPM operation without cooldown and low-RON fuel increase HPFP and turbo stress, making fuel quality and operational discipline critical.
Analysis derived from Mercedes-Benz technical bulletins (2013-2017) and UK DVSA failure statistics (2014-2018). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about MERCEDES-BENZ M157981.
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