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Mercedes C-Class W204 Reliability Guide (2007–2014)
The Mercedes C-Class W204, produced from 2007 to 2014, is one of the brand’s most popular premium sedans. It earned its reputation thanks to strong comfort, understated styling, and a wide range of engines. This generation is also widely regarded as significantly more reliable than the W203 it replaced.
That said, not all engines are created equal. Some powertrains are clearly worth choosing, while others are best avoided. This reliability guide to the Mercedes C-Class W204 will help you make the right choice when buying used.
Already own a Mercedes C-Class W204 or thinking about buying one? Explore our selection of Mercedes accessories and customization parts in our online store. Panamericana grilles, black badges, CarPlay / Android Auto modules, and premium interior upgrades—everything you need to modernize and enhance your C-Class.
See our Mercedes C-Class W204 collection
Gasoline Engine Reliability
C180 / C200 CGI (1.8 Turbo – M271)
Strengths:
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Smooth and reasonably fuel-efficient.
Known issues:
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Weak timing chain (metallic noise on cold start, risk of failure).
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Excessive oil consumption on some vehicles.
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Sensitive injectors and ignition coils.
Recommendation: Choose models produced after 2010, which benefit from updated components.
C250 (1.8 Turbo – M271)
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Shares the same weaknesses as the C180 and C200 (timing chain and oil consumption).
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More powerful, but not necessarily more reliable.
C350 (3.5L V6 – M272)
Strengths:
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More robust than the 1.8L engines.
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Smooth, durable, and well-suited to the chassis.
Known issues:
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Balance shaft gear wear (mainly on pre-2008 models).
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Occasional mass airflow sensor and electronic sensor failures.
Recommendation: Models from 2009 onward offer very solid reliability.
C63 AMG (6.2L V8 – M156)
Strengths:
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Legendary naturally aspirated V8.
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Very strong mechanical design.
Watch out for:
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Cylinder head and valvetrain issues on some early engines.
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High oil consumption.
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Extremely expensive maintenance and running costs.
Diesel Engine Reliability
C200 CDI / C220 CDI / C250 CDI (2.1L Diesel – OM646, then OM651)
Strengths:
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Fuel-efficient and long-lasting, especially the OM646.
OM651-specific issues (post-2009):
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Fragile injectors.
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EGR valve and DPF clogging with frequent city driving.
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Timing chain noise on some engines.
Recommendation: The OM646 (pre-2009) is the safest and most reliable choice.
C320 CDI / C350 CDI (3.0L V6 Diesel – OM642)
Strengths:
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Very strong, torquey, and reliable engine.
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Excellent for highway driving and high mileage.
Common issues:
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Swirl flap wear in the intake system.
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Differential pressure sensors for the DPF.
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Frequent oil leaks (valve covers, oil cooler seals, oil pan).
Electronics and General Components
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Infotainment systems (COMAND, Audio 20): occasional software glitches.
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7G-Tronic automatic transmission: generally reliable, but fluid changes every 60,000 km (around 40,000 miles) are essential.
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Onboard electronics: ABS, ESP, and parking sensors can fail over time.
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Front suspension: control arm bushings and ball joints tend to wear relatively quickly.
Verdict: Which Mercedes C-Class W204 Should You Buy?
Best choices:
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OM646 diesel (C220 CDI up to 2009) for long-term durability.
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C350 gasoline V6 for a good balance of reliability and performance.
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C350 CDI for high-mileage drivers seeking torque and efficiency.
Engines to avoid:
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1.8 CGI gasoline engines built before 2010 due to timing chain issues.
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OM651 diesel if used mainly for short city trips, as it is prone to clogging.
Pre-Purchase Tips
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Ask for complete service records, preferably from Mercedes-Benz dealerships.
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Carefully check the timing chain on 1.8 CGI gasoline engines.
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Test the automatic transmission: shifts should be smooth, with no hesitation or jolts.
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Verify all electronic systems (navigation, climate control, parking sensors).
FAQ – Used Mercedes C-Class W204
Is the Mercedes C-Class W204 reliable?
Yes. Overall, it is a reliable platform, especially compared to earlier generations such as the W203 and W202.
What is the best gasoline engine?
The 3.5L V6 (C350) is more robust and more refined than the 1.8 CGI engines.
What is the best diesel engine?
The 2.1L CDI OM646 (up to 2009) and the V6 OM642 are the most dependable options.
Is the automatic transmission reliable?
Yes. The 7G-Tronic is durable when serviced regularly, with fluid changes every 60,000 km.
In summary
The Mercedes C-Class W204 is a dependable and well-built premium sedan, provided you choose the right engine and verify its maintenance history carefully.
Parts and accessories to keep your Mercedes modern
We offer a selection of car parts designed for Mercedes owners:
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Replacement steering-wheel multifunction buttons (OEM-style) — swap worn or sticky buttons to restore controls and avoid intermittent electrical issues.
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CarPlay / Android Auto retrofit modules — reduce reliance on aging infotainment hardware while improving daily usability (and often avoiding repeated software-related service trips).
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Mirror caps & exterior trims (carbon / gloss black) — cosmetic, but they can be replaced easily if originals are cracked or corroded, improving the car’s perceived value.
All items are OE-fitment minded, shipped with free delivery and backed by a 1-year guarantee, so you can modernize and maintain your Mercedes without surprises.