Mercedes-Benz M157 Engine: Issues & Details Explained

M157 Engine
M157 Engine

Mercedes‑AMG M157 5.5 L Biturbo V8 (2010–2019): Overview, Issues & Care

The M157, launched in 2010 as AMG’s first 5.5 L biturbo V8, powers flagship models like the S63, E63, CLS63, G63, and SL63. It’s based on the M278 architecture but richly enhanced for performance, offering up to 585 hp and 900 Nm of torque

The M157 blends raw muscle with cutting-edge German engineering, making it one of the most exciting engines of the last decade. But like any high-performance powertrain, it has its fair share of pros, quirks, and concerns.

Let’s dive into the M157’s strengths, specifications, and known issues to help you understand what makes this engine special and what to watch out for.

M157 Engine
M157 Engine

M157 Engine Reliability

The M157 is generally regarded as a reliable engine especially when maintained properly. It uses forged internals, advanced direct injection, and twin turbochargers, offering a blend of longevity and performance.

That said, this engine isn’t low maintenance. It thrives on high-quality oil, timely servicing, and careful driving habits. Owners who follow Mercedes-Benz’s recommended service schedule and avoid aggressive cold starts often enjoy trouble-free performance well into high mileage.

However, the M157 engine is not without its weaknesses. Components like the timing chain system, camshaft adjusters, and valve cover gaskets have been known to fail over time, especially in vehicles with inconsistent maintenance histories.

M157 Engine
M157 Engine

Despite this, many enthusiasts consider the M157 more reliable than its predecessor (the naturally aspirated M156) due to improvements in torque delivery and internal efficiency.

M157 Engine Specifications: Raw Numbers, Refined Output

SpecDetails
Displacement5,461 cc (98 × 90.5 mm)
Power Output525–585 hp (varies by model/tuning)
Torque700–900 Nm
ValvetrainDOHC, VVT, direct injection (piezoceramic injectors)
TurbochargersTwin Garrett MGT2260MSL, up to 1.3 bar boost
Block / HeadAluminum alloy block & head, forged internals
Oil Capacity~8.5 L, recommended 0W‑40 factory oil
DriveAMG SPEEDSHIFT MCT 7-speed or 7G‑Tronic automatic

The M157 produces impressive low-end torque, offering explosive acceleration and effortless highway cruising. Models equipped with the optional AMG Performance Package crank power up to 577 horsepower and 664 lb-ft of torque.

M157 Oil Capacity

The M157 engine requires a significant volume of oil to properly lubricate its high-performance components. The oil capacity for the M157 is approximately 8.5 liters (about 9.0 quarts), including the oil filter.

Using high-quality synthetic motor oil that meets Mercedes-Benz’s 229.5 specification is essential for maintaining engine health and performance. Regular oil changes are especially critical for the M157 due to the high temperatures and stresses placed on the engine during spirited driving.

Skipping oil changes or using the wrong oil type can accelerate wear on the turbos and internal components. For best results, follow the service interval recommended by Mercedes or shorten it under heavy usage conditions.

Common M157 Engine Problems & Solutions

IssueSymptomsFix / Maintenance
Timing chain & tensioner wearTicking noise, rattling common high-mileage issue Replace tensioners, chains during major service (~150k mi)
Coolant & water-pump leaksOverheat / coolant lossInspect hoses/pump; replace seals promptly
Oil leaks (valve cover/filters)Puddles under engine; burning oil smellReplace gaskets, tighten filter housing
Cylinder scoring (1 & 5)Misfire, low compressionCompression test; consider engine rework if damaged
Camshaft solenoid & sensor faultsCheck-engine light, starting/run issuesReplace faulty solenoids/sensors
Thermostat / coolant flap failuresErratic temp gauge or heat cyclesReplace components before overheating occurs
Turbocharger wearWhistling noise, no peak boostCheck intercooler and hoses; rebuild or replace turbo

Engine Check Light Was On: Here’s What Really Caused It

M157 Engine Problems
M157 Engine Problems
  • – Oil & filter changes: every 10k mi using OEM spec 0W‑40
  • – Spark plugs: every 30–40k mi
  • – Inspect timing chain & tensioners every 100–150k mi
  • – Cooling system check: include hoses, thermostat & water pump
  • – Compression testing if misfires or performance drops
  • – Replace gaskets/seals at first sign of leaks
  • – Turbo inspection: check boost levels and hoses regularly

What Cars Have the M157 Engine?

The M157 engine was used in a wide range of AMG models between 2011 and 2019, including:

M157 Engine
M157 Engine

=> Mercedes-Benz E63 AMG (W212)
Both sedan and wagon variants, offered with RWD and 4MATIC.

=> Mercedes-Benz CLS63 AMG (W218)
A performance version of the stylish four-door coupe.

=> Mercedes-Benz S63 AMG (W221 and early W222)
Luxurious performance in a flagship sedan package.

=> Mercedes-Benz CL63 AMG (C216)
Grand touring coupe with twin-turbo torque.

=> Mercedes-Benz G63 AMG (W463 pre-2018)
Iconic boxy SUV with an aggressive V8 soundtrack.

=> Mercedes-Benz ML63 AMG (W166)
High-performance SUV combining luxury and brute force.

=> Mercedes-Benz GL63 AMG (X166)
A three-row powerhouse for family thrill seekers.

=> Mercedes-Benz SL63 AMG (R231, pre-facelift)
A convertible blend of performance and open-air luxury.

Conclusion: Should You Own an M157-Powered Mercedes?

If you crave neck-snapping acceleration, deep V8 sound, and aggressive AMG styling, the M157 is an outstanding engine to own. It offers supercar performance with the comfort and practicality of a daily driver provided you’re prepared for its maintenance needs.

Regular servicing, quality oil, and addressing known issues early will ensure the M157 engine rewards you with thrilling performance for years to come.

Whether you’re buying used or already own one, knowing the specs, common problems, and maintenance needs will help you get the most out of this engineering masterpiece.

Frequently Asked Questions

How long does the M157 last?

With diligent maintenance, it can exceed 200,000 mi but timing chain and coolant issues must be monitored.

Why does my M157 leak oil?

High temperatures and worn gaskets are common causes replace valve-cover and oil-filter housing seals early.

Is cylinder scoring a big issue?

Yes, especially on cylinders 1 & 5. Address early via compression testing; heavy scoring may require engine rebuild.

Should I be worried about turbo failure?

Turbos are generally durable if oil changes are timely; inspect hoses and intercoolers to prevent boost loss.