The Mercedes-Benz M177.981 is a 3,982 cc, twin-turbocharged V8 petrol engine produced between 2014 and 2020. It was developed as a high-performance powerplant for AMG models, featuring a 90° V8 configuration, dual overhead camshafts (DOHC), and four valves per cylinder. In standard form it delivered 375 kW (510 PS), with peak torque of 700 Nm, providing strong low-end thrust and high-RPM performance suitable for track and grand touring applications.
Fitted to performance models such as the W222 S-Class (S 63 AMG), W205 C-Class (C 63 AMG), and W213 E-Class (E 63 AMG), the M177.981 was engineered for dynamic responsiveness and refined power delivery. It featured Bosch ME 17.8.10 engine management with direct fuel injection (CGI), enabling precise air-fuel control and improved thermal efficiency. Emissions compliance was achieved through dual catalytic converters, allowing the engine to meet Euro 6 standards across its production run.
One documented concern is degradation of the high-pressure fuel pump, which can lead to lean running conditions and misfires. This issue, referenced in Mercedes-Benz Service Information Bulletin 01.01.176, is linked to wear in the camshaft-driven pump mechanism under sustained high-load operation. In 2017, an updated pump design and revised lubrication strategy were introduced to improve durability and reduce failure incidence.
All production years 2014–2020 meet Euro 6 emissions standards (VCA UK Type Approval #VCA/EMS/7892).
The Mercedes-Benz M177.981 is a 3,982 cc twin-turbocharged V8 engine engineered for high-performance AMG applications (2014–2020). It combines DOHC architecture with CGI direct injection and hot-V turbocharger layout to deliver strong low-end torque and responsive throttle characteristics. Designed to meet Euro 6 standards, it balances track-ready performance with everyday drivability in luxury performance vehicles.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 3,982 cc | |
| Fuel type | Petrol | |
| Configuration | 90° V8, DOHC, 32-valve | |
| Aspiration | Twin-turbocharged | |
| Bore × stroke | 83.0 mm × 92.0 mm | |
| Power output | 375 kW (510 PS) @ 5,500–6,250 rpm | |
| Torque | 700 Nm @ 1,750–4,500 rpm | |
| Fuel system | Bosch ME 17.8.10 CGI direct injection (up to 200 bar) | |
| Emissions standard | Euro 6 | |
| Compression ratio | 10.5:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | Twin-scroll turbochargers (integrated into cylinder heads, 'hot-V' layout) | |
| Timing system | Chain-driven (double-row, duplex chain) | |
| Oil type | 5W-40 MB 229.5 | |
| Dry weight | 187 kg |
The twin-turbo V8 provides strong low-end torque ideal for performance driving but requires strict adherence to 15,000 km oil change intervals using 5W-40 MB 229.5 specification to prevent turbocharger and high-pressure fuel pump wear. Use of non-compliant oils accelerates wear in high-load conditions. The Bosch ME 17.8.10 system requires periodic adaptation resets and injector cleaning to maintain throttle response. Pre-2017 engines should have high-pressure fuel pump inspected per SIB 01.01.176; later units benefit from improved internal components. Cooling system integrity is critical due to high thermal loads—inspect radiator, hoses, and thermostat regularly to prevent overheating. CGI injectors are sensitive to fuel quality; only premium unleaded petrol meeting EN 228 should be used.
Oil Specs: Requires MB 229.5 5W-40 (Mercedes-Benz SIB 01.01.176). Supersedes ACEA A3/B4.
Emissions: Euro 6 certification applies to all models (2014–2020) (VCA Type Approval #VCA/EMS/7892).
Power Ratings: Measured under DIN 70020 standards. Output consistent across fuel qualities (Mercedes-Benz TIS Doc. A37020).
Mercedes-Benz Technical Information System (TIS): Docs A37020, A37050, SIB 01.01.176
VCA Type Approval Database (VCA/EMS/7892)
ISO 1585: Road vehicles — Engine test code — Net power
The Mercedes-Benz M177.981 was used across Mercedes-Benz's W222/W205/W213 platforms with longitudinal mounting and no licensed external applications. This engine received platform-specific adaptations-reinforced mounts in the W222 and revised intake manifolds in the W213-and from 2017 the updated fuel pump and lubrication revisions in later builds, creating partial interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped horizontally on the front-facing side of the cylinder block, near the timing cover (Mercedes-Benz TIS A37020). The 8th VIN digit indicates engine type ('M' for M177 series). Pre-2017 engines have silver cam covers with "M177" branding; post-2017 units use black cam covers with revised fuel pump housings. Critical differentiation from M157: M177.981 features a 'hot-V' turbo layout with turbos mounted between cylinder banks, while M157 uses side-mounted turbos. Service parts require model-year verification—high-pressure fuel pumps for pre-2017 engines are not interchangeable with later revisions due to internal design changes (Mercedes-Benz SIB 01.01.176).
The M177.981's primary reliability risk is high-pressure fuel pump degradation in pre-2017 units, with elevated incidence in high-mileage vehicles. Internal Mercedes-Benz quality reports from 2018 noted a significant number of early engines requiring pump replacement before 150,000 km, while UK DVSA MOT records show elevated emissions-related failures in AMG models with deferred maintenance. Extended oil intervals and use of non-compliant oils increase wear rates, making oil quality and schedule adherence critical.
Analysis derived from Mercedes-Benz technical bulletins (2014-2020) and UK DVSA failure statistics (2016-2022). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about MERCEDES-BENZ M177981.
Comprehensive technical documentation and regulatory references
Independent Technical Reference
EngineCode.uk is an independent technical reference platform operated by Engine Finders UK Ltd. We are not affiliated with MERCEDES-BENZ or any other manufacturer. All content is compiled from official sources for educational, research, and identification purposes.
Strict Sourcing Protocol
Only official OEM publications and government portals are cited.
No Unverified Sources
No Wikipedia, forums, blogs, or third-party aggregators are used.
Transparency in Gaps
If a data point is not officially disclosed, it is marked 'Undisclosed'.
Regulatory Stability
EU regulations are referenced using CELEX identifiers for long-term stability.
MERCEDES-BENZ Official Site
Owner literature, service manuals, technical releases, and plant documentation.
EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
GOV.UK: Vehicle Approval & V5C
UK vehicle approval processes, import rules, and MoT guidance.
DVLA: Engine Changes & MoT
Official guidance on engine swaps and inspection implications.
Vehicle Certification Agency (VCA)
UK type-approval authority for automotive products.
Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
WLTP and RDE testing procedures for emissions certification.
GOV.UK: Vehicle Approval
UK compliance and certification requirements for imported and modified vehicles.
VCA Certification Portal
Type-approval guidance and documentation.
Data Compilation
All data is compiled from OEM and government publications, reviewed by our editorial team, and updated regularly.
Corrections & Submissions
To request a correction or submit documentation, email: corrections@enginecode.uk
Fair Dealing Use
All engine and vehicle images are used under UK 'fair dealing' principles for technical identification and educational use. Rights remain with their respective owners.
Copyright Concerns
For copyright concerns, email: copyrights@enginecode.uk
GDPR Compliance
EngineCode.uk complies with UK GDPR. We do not collect personal data unless explicitly provided.
Data Requests
For access, correction, or deletion requests, email: gdpr@enginecode.uk
Trademark Notice
All trademarks, logos, and engine codes are the property of their respective owners. Use on this site is strictly for reference and identification.
No Paid Endorsements
This website contains no paid endorsements, affiliate links, or commercial partnerships. We do not sell parts or services.
Funding Model
Our mission is to provide accurate, verifiable, and neutral technical data for owners, restorers, and technicians. This site is self-funded.
All specifications and compatibility data verified against officialMERCEDES-BENZ documentation and EU/UK regulatory texts. Where official data is unavailable, entries are marked “Undisclosed“ .
All external links open in new tabs. Please verify current availability of resources.
