Mercedes CL63 AMG M157

The Mercedes CL63 AMG M157 has a reliability score of 44/100, rated "RISKY". Fast, brutal, and expensive to own

The most frequently reported issues are Timing Chain and Balance Shaft Failure, Cylinder Scoring, Cam Solenoid (Camshaft Adjuster Solenoid) Failure, Valve Timing Cover Oil Leak, among others. See the Known Issues section above for symptoms, affected mileage, and repair costs.

Yes, this is a documented issue on the M157, typically appearing around 80,000-160,000 km. The M157 is known to suffer from timing chain sprocket wear and balance shaft failures. When the timing mechanism fails it can cause bent intake valves and camshaft sync loss, leading to catastrophic engine damage. Typical repair cost: €3,000-8,000. DIY difficulty: Expert only.

Yes, this is a documented issue on the M157, typically appearing around 60,000-150,000 km. The M157 is specifically cited by the community as prone to cylinder bore scoring, particularly when not driven hard enough to keep rings seated, or due to insufficient oil maintenance. Can result in full engine rebuild or replacement. Typical repair cost: €5,000-15,000. DIY difficulty: Expert only.

Yes, this is a documented issue on the M157, typically appearing around 60,000-120,000 km. Cam solenoids are among the most commonly replaced components on the M157. They affect variable valve timing operation and can cause rough running, misfires and fault codes when they fail. Typical repair cost: €300-900. DIY difficulty: Moderate.

Yes, this is a documented issue on the M157, typically appearing around 50,000-120,000 km. The valve timing cover (part A2760150201) is a known leak point on the M157. Located at the front of the engine, it is accessible once the air intakes are removed. Considered a widespread and well-documented issue. Typical repair cost: €400-1,200. DIY difficulty: Moderate.

Yes, this is a documented issue on the M157, typically appearing around 80,000-180,000 km. Community reports specifically flag harness issues as one of the two main problem areas on the M157. Wiring insulation can crack and fail near hot engine bay areas, causing intermittent faults, misfires and sensor errors. Typical repair cost: €800-2,500. DIY difficulty: Hard.

Yes, this is a documented issue on the M157, typically appearing around 60,000-120,000 km. Thermostats are listed among the most commonly replaced items on the M157. Failure can cause overheating or running too cold, both of which accelerate engine wear. Typical repair cost: €200-600. DIY difficulty: Moderate.

The CL63 AMG M157 is a high-performance vehicle with well-known mechanical vulnerabilities that must be respected, not ignored. Timing chain, cylinder scoring, and wiring harness issues can turn this car into a money pit if you buy the wrong example or maintain it incorrectly. Only buy with full documented service history, a clean compression test, and ideally an extended third-party warranty in place. Budget at least €9,000-15,000 over the first three years of ownership for maintenance and unexpected repairs to enjoy it without financial stress.

The power difference between the standard CL63 and the Performance Package version comes from an ECU and boost tune, not from stronger internals, so it does not change the underlying risk of timing chain, cylinder scoring or harness failure. Do not choose based on the hp figure. Choose based on documented oil change history, a clean cold start (no rattle), and a passed compression/leak-down test, since these tell you far more about the individual car's condition than which tune it left the factory with.

Before buying, check: Commission a leak-down and compression test on all 8 cylinders to check for cylinder scoring before purchase; Start the engine cold and listen carefully for timing chain rattle during the first 10-15 seconds; Remove air intake ducting and visually inspect the front timing cover for oil leaks; Run a full OBD-II diagnostic scan to check for camshaft solenoid, timing, and wiring fault codes; Verify full documented service history with oil changes no longer than 8,000 km intervals using approved spec oil.

There's no fixed mileage limit, it depends on maintenance. The parts worth budgeting for proactively are: Timing chain and balance shaft sprockets (80,000 km), Valve timing cover gasket/seal (60,000 km), Cam solenoids (x4) (80,000 km), Engine wiring harness (100,000 km). Engines that clear these checkpoints with documented maintenance commonly continue well beyond typical ownership periods.

Estimated ownership cost is €9,000-18,000 over 3 years including routine maintenance, consumables and provision for known high-risk components (timing chain, cylinder scoring, wiring harness), based on known issues and typical service needs.

Owners report real-world fuel consumption of around 14.7 L/100km.

Community-reported real-world usage suggests changing oil every 8,000 km using Mercedes-Benz 229.5 or 229.51 approved 0W-40 or 5W-40 fully synthetic, often more conservative than the official service schedule.

The M157 is also found in: Mercedes-Benz E63 AMG (W212), Mercedes-Benz S63 AMG (W221/W222), Mercedes-Benz ML63 AMG (W166), Mercedes-Benz GL63 AMG (X166), Mercedes-Benz SL63 AMG (R231), Mercedes-Benz G63 AMG (W463).

Fast, brutal, and expensive to own The biggest recurring complaint is Timing Chain and Balance Shaft Failure. Mixed to cautious. Enthusiasts love the engine's performance but repeatedly warn about timing chain, cylinder scoring and harness issues. Multiple forum contributors advise always securing a warranty on any used M157 purchase. Some owners report years of reliable service with strict maintenance discipline.