The Mercedes — Benz M273.960 is a 5,461 cc, 90° V8 naturally aspirated petrol engine produced between 2005 and 2011. It features dual overhead camshafts (DOHC), variable valve timing (VVT), and sequential multi — point fuel injection. Designed for high — end luxury applications, it delivers 258 kW (351 PS) and 510 Nm of torque, with a focus on smooth power delivery and acoustic refinement. Its architecture supports electronic throttle control and adaptive ignition mappi…
All production years 2005–2011 meet Euro 4 emissions standards (VCA UK Type Approval #VCA/EMS/5679).
The Mercedes-Benz M273.960 is a 5,461 cc V8 naturally aspirated petrol engine engineered for luxury sedan and grand tourer applications (2005–2011). It combines dual overhead camshafts with variable valve timing to deliver linear power delivery and high-speed refinement. Designed to meet Euro 4 standards, it balances performance with regulatory compliance and long-term drivability.
| Parameter | Value | Source |
|---|---|---|
Displacement | 5,461 cc | |
Fuel type | Petrol | |
Configuration | 90° V8, DOHC, 32-valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 96.9 mm × 92.4 mm | |
Power output | 258 kW (351 PS) | |
Torque | 510 Nm @ 2,700–4,250 rpm | |
Fuel system | Sequential multi-point fuel injection (ME 9.7 ECU) | |
Emissions standard | Euro 4 | |
Compression ratio | 10.5:1 | |
Cooling system | Water-cooled | |
Turbocharger | N/A | |
Timing system | Dual chain (primary and secondary), non-interference design | |
Oil type | MB 229.5 (SAE 5W-40) | |
Dry weight | 205 kg |
The Mercedes-Benz M273.960 was used across Mercedes-Benz's W211, W221, and R230 platforms with longitudinal mounting and no licensed external applications. This engine received platform-specific adaptations-variable intake manifolds in the W221 and revised exhaust manifolds in the R230-and from 2008 the updated W211 facelift models adopted revised hydraulic lash adjusters, creating service part interchange limits. All adaptations are documented in OEM technical bulletins.
The M273.960's primary reliability risk is hydraulic lash adjuster wear on early builds, with elevated incidence in mixed urban driving. Internal Mercedes-Benz quality reports from 2009 indicated a significant number of pre-2008 engines required follower replacement before 100,000 km, while UK DVSA MOT records show cam-related faults contribute to emissions failures in high-mileage units. Frequent cold starts and extended short trips increase wear risk, making oil quality and interval adherence critical.
Analysis derived from Mercedes-Benz technical bulletins (2007-2012) and UK DVSA failure statistics (2015-2023). Repair procedures should follow manufacturer guidelines.
The most common questions about engine codes, what they mean, how to find them and how this database works
The M273.960 is fundamentally robust with strong build quality, but early models (2005–2007) are prone to cam follower wear. Later revisions (post-2008) incorporated improved hydraulic lash adjusters, significantly enhancing durability. When maintained with correct MB 229.5 oil and timely servicing, these engines reliably exceed 150,000 km. Neglecting oil changes or using non-compliant fluids increases risk of valvetrain damage.
Primary issues include camshaft follower wear (especially pre-2008), intake manifold flap linkage failure, valve cover oil leaks, and ignition coil degradation. These are well-documented in Mercedes-Benz service bulletins. Secondary concerns include fuel injector coking and CCV system blockages. Regular inspection and OEM-specified maintenance mitigate most risks effectively.
The M273.960 5.5L V8 was used in several flagship models: E500 (W211), S500 (W221), CL500 (C215), and SL500 (R230), produced between 2005 and 2011. It was not licensed to other manufacturers. All applications meet Euro 4 emissions standards, with minor tuning differences across platforms to suit weight and aerodynamics.
Yes, though gains are limited due to its naturally aspirated design. ECU remapping can yield +15–25 kW by optimizing throttle response and ignition timing. Supporting modifications like high-flow exhausts and cold-air intakes enhance results. However, aggressive tuning without mechanical upgrades risks exceeding component tolerances. Stage 1 tuning is generally safe on well-maintained engines.
Fuel consumption is moderate for a 5.5L V8. In combined driving, expect 11.5–13.5 L/100km (21–25 mpg UK). Highway cruising can achieve ~9.0 L/100km (31 mpg UK), while city driving may exceed 15 L/100km (19 mpg UK). Real-world economy depends heavily on driving style and vehicle weight. No official hybrid or economy modes were offered.
No. The M273.960 uses a non-interference valvetrain design. If the timing chain fails or jumps, the pistons will not contact the valves, preventing catastrophic internal damage. However, timing chain replacement is still recommended at 180,000 km or as condition dictates to maintain synchronization and prevent secondary issues.
Mercedes-Benz specifies SAE 5W-40 oil meeting MB 229.5 standard. This low-ash, high-shear-stability formulation is critical for protecting hydraulic lash adjusters and preventing sludge buildup. Oil changes should occur every 15,000 km or annually. Using non-compliant oils increases risk of cam follower wear and premature engine wear.
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.