Mercedes-Benz CLK C209
Weaknesses, engine ratings and buying advice
457–525 PS
6.2L V8 AMG Benzin
CLK 63 AMG — V8 Coupé of the Old School
Legendary!457–525 PS
6.2L V8 AMG Benzin
10 weaknesses
Stay Away!Body Variants
The Mercedes-Benz CLK C209 is available as Cabrio and Coupé — choose your body type for specific insurance data:
Generations
Engine Overview
The Mercedes-Benz CLK C209 is available with 13 engine variants — from 120 to 525 hp. 3 variants had engine changes — the model year is crucial.
The Mercedes-Benz CLK 220 CDI (Diesel, 150 PS) has the OM651DE22 (2.1L Diesel) — rated: "Stay Away!", 6 known weaknesses.
The Mercedes-Benz CLK 270 CDI (Diesel, 163–170 PS) has the OM612 (2.7L 5-Zyl Diesel) — rated: "Stay Away!", 6 known weaknesses.
The Mercedes-Benz CLK 320 CDI (Diesel, 224 PS) has the OM642 (3.0L V6 Diesel) — rated: "Stay Away!", 7 known weaknesses.
The Mercedes-Benz CLK 200 CGI (Benziner, 163–170 PS) comes with 2 different engines: M271 (2003–2005, Stay Away!) und M271 (2003–2005, Stay Away!). Pay attention to the model year for the CLK 200 CGI!
The Mercedes-Benz CLK 200 Kompressor (Benziner, 163–184 PS) comes with 3 different engines: M271 (2002–2006, Stay Away!) und M271 (2002–2006, Stay Away!) und M271 (2006–2010, Stay Away!). Pay attention to the model year for the CLK 200 Kompressor!
The Mercedes-Benz CLK 240 (Benziner, 163–170 PS) has the M112 (3.2L V6) — rated: "Be Careful", 7 known weaknesses.
The Mercedes-Benz CLK 280 (Benziner, 231 PS) has the M272 (3.0-3.5L V6) — rated: "Stay Away!", 6 known weaknesses.
The Mercedes-Benz CLK 320 (Benziner, 218 PS) has the M112 (3.2L V6) — rated: "Be Careful", 7 known weaknesses.
The Mercedes-Benz CLK 350 (Benziner, 272 PS) has the M272 (3.0-3.5L V6) — rated: "Stay Away!", 6 known weaknesses.
The Mercedes-Benz CLK 500 (Benziner, 306–387 PS) comes with 2 different engines: M113 (2002–2006, Be Careful) und M273 (2006–2010, Stay Away!). Pay attention to the model year for the CLK 500!
The Mercedes-Benz CLK 55 AMG (Benziner, 367 PS) has the M113 (4.3-5.4L V8) — rated: "Be Careful", 10 known weaknesses.
The Mercedes-Benz CLK 63 AMG (Benziner, 481 PS) has the M156 (6.2L V8 AMG) — rated: "Stay Away!", 10 known weaknesses.
The Mercedes-Benz CLK 63 AMG Black Series (Benziner, 507 PS) has the M156 (6.2L V8 AMG) — rated: "Stay Away!", 10 known weaknesses.
Vehicle Weaknesses
| Weakness | Cost | |
|---|---|---|
| 5G-Tronic: Coolant Ingress via Valeo Cooler Valeo transmission oil heat exchanger on pre-facelift models up to 09/2003 develops leaks. Coolant enters the transmission and destroys the clutch packs. Symptom: humming and juddering at low revs. Symptoms: Humming and juddering under light acceleration at low rpm, cloudy transmission fluid from 70,000 km | High |
Alternatives
Audi RS6 C6
Mittelklasse (2008–2010)
Audi S4 B8
Mittelklasse (2008–2016)
VW Passat CC I
Mittelklasse (2008–2012)
Audi A4 B8
Mittelklasse (2007–2015)
Audi A5 8T
Mittelklasse (2007–2016)
Ford Mondeo BA7
Mittelklasse (2007–2014)
Known Problems and Issues
A total of 79 weaknesses have been documented for the Mercedes-Benz CLK C209 (2002–2010) — 73 engine-related and 6 vehicle-related. 7 problem engines: OM651DE22 (2.1L Diesel), M271 (1.8L Kompressor), M272 (3.0-3.5L V6), M273 (5.0-5.5L V8), OM612 (2.7L 5-Zyl Diesel), OM642 (3.0L V6 Diesel), M156 (6.2L V8 AMG). Typical issues affect Gearbox, Electronics, Body, Brakes.
CLK (OM612, 2002–2005) — Stay Away!: "Black Death" -- injector seal failure with tar formation, EGR cooler fails -- coolant in intake, Cylinder head crack -- coolant loss under load. Power: 163–170 PS.
CLK (OM651DE22, 2005–2010) — Stay Away!: Chain Tensioner Seal Leaking — Recall, Timing Chain Stretch (Simplex Chain), Piezo Injector Faults. Power: 150 PS.
CLK (OM642, 2005–2010) — Stay Away!: Oil Cooler Gaskets Leaking — Oil and Coolant Loss, Swirl Flap Linkage Breaks — Plastic Joint Fails, Injector Seal Leaking — Soot Deposits and Diesel in Oil. Power: 224 PS.
CLK (M111, 1998–2003) — Be Careful: Head Gasket Ages and Leaks, Supercharger Magnetic Clutch Fails, Ignition Coils Wear Out Due to Neglected Spark Plugs. Power: 136 PS.
CLK (M112, 1998–2003) — Be Careful: Camshaft Adjuster Leaks Oil into Wiring Harness, Intake Manifold Vacuum Hose Breaks, Valve Cover Gasket and Front Cover Gasket Leaking. Power: 218 PS.
CLK (M113, 1999–2003) — Be Careful: Vibration Damper/Pulley — Rubber Hardens, Rear Crankshaft Seal Leaking, Engine Mounts Worn Prematurely. Power: 279 PS.
CLK (M111, 2000–2003) — Be Careful: Head Gasket Ages and Leaks, Supercharger Magnetic Clutch Fails, Ignition Coils Wear Out Due to Neglected Spark Plugs. Power: 163 PS.
CLK (M111, 2000–2003) — Be Careful: Head Gasket Ages and Leaks, Supercharger Magnetic Clutch Fails, Ignition Coils Wear Out Due to Neglected Spark Plugs. Power: 193–197 PS.
CLK (M112, 2002–2005) — Be Careful: Camshaft Adjuster Leaks Oil into Wiring Harness, Intake Manifold Vacuum Hose Breaks, Valve Cover Gasket and Front Cover Gasket Leaking. Power: 163–170 PS.
CLK (M113, 2002–2006) — Be Careful: Vibration Damper/Pulley — Rubber Hardens, Rear Crankshaft Seal Leaking, Engine Mounts Worn Prematurely. Power: 306 PS.
CLK (M113, 2002–2006) — Be Careful: Vibration Damper/Pulley — Rubber Hardens, Rear Crankshaft Seal Leaking, Engine Mounts Worn Prematurely. Power: 367 PS.
CLK (M271, 2002–2006) — Stay Away!: Timing Chain Stretches Prematurely, Camshaft Adjuster Leaks — Oil in Wiring Harness, Camshaft Adjuster Leaks Oil into Connector. Power: 163–170 PS.
CLK (M272, 2005–2010) — Stay Away!: Balance Shaft Sprocket Wears Prematurely, Timing Chain Stretches and Damages Timing, Camshaft Adjuster Leaks — Wiring Harness Contaminated. Power: 231 PS.
CLK (M272, 2005–2010) — Stay Away!: Balance Shaft Sprocket Wears Prematurely, Timing Chain Stretches and Damages Timing, Camshaft Adjuster Leaks — Wiring Harness Contaminated. Power: 272 PS.
CLK (M271, 2006–2010) — Stay Away!: Timing Chain Stretches Prematurely, Camshaft Adjuster Leaks — Oil in Wiring Harness, Camshaft Adjuster Leaks Oil into Connector. Power: 184 PS.
CLK (M273, 2006–2010) — Stay Away!: Balance shaft sprocket — same weakness as M272, Camshaft Adjuster Leaking — Oil in Wiring Harness, Valve cover gaskets leaking on both sides. Power: 387 PS.
CLK (M156, 2006–2010) — Stay Away!: Head Bolt Corrosion — Coolant in Combustion Chamber, Camshaft Wear — Cold-Start Lubrication Deficit, Camshaft Adjuster — Locking Plate Wears Out. Power: 481 PS.
CLK (M156, 2007–2009) — Stay Away!: Head Bolt Corrosion — Coolant in Combustion Chamber, Camshaft Wear — Cold-Start Lubrication Deficit, Camshaft Adjuster — Locking Plate Wears Out. Power: 507 PS.
What to watch out for with the Mercedes-Benz CLK? See the detailed listing of all engine and vehicle weaknesses in the sections above.
Frequently Asked Questions
What problems and weaknesses does the Mercedes-Benz CLK C209 have? +
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Which engine is recommended? +
Which Mercedes-Benz CLK C209 engine is the most fun? +
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Last updated: February 2026 · All information without guarantee