CLK-CLASS

Mercedes-Benz CLK-Class Reliability

Owners filed 227 complaints — 1.39 per production run against 3.73 for the market. The typical failure comes at 7 years, and the basic warranty runs out at 4.

NHTSA owner complaints · 227 complaints · 2002–2009 · Updated Sep 19, 2026
Quick answer

The Mercedes-Benz CLK-Class draws 1.39 complaints per production run against 3.73 for the average car — better than typical. The worst model year is 2006 at 1.54 complaints per run; the best is 2009 at 1 — a 1.5-fold gap between two cars wearing the same badge. Failures cluster at 7 years, so only 14.8% of them fall inside the 4-year basic warranty.

Mercedes-Benz CLK-Class years to avoid — and the best ones

The Mercedes-Benz CLK-Class year to avoid is 2006, at 1.54 complaints per production run. The best is 2009 at 1 — 1.5 times cleaner for a car wearing the same badge. Both figures are rates, not totals: a raw count only tells you which year sold well, so the best-selling year always looks like the worst car. Dividing by the number of production runs strips sales volume out and leaves the fault rate.

FIG.01·Mercedes-Benz CLK-Class — complaint rate by model year
Model yearPer runComplaintsRunsEnough history?
2009199yes
20081.251512yes
20071.484933yes
20061.544328yes
20051.363022yes
20041.383626yes
20031.422719yes
20021.131816yes
ROWS 8·SOURCE NHTSA complaints, grouped by VIN production run

Among the 8 Mercedes-Benz CLK-Class years with enough history, the three to walk away from are 2006, 2007, 2004; the three worth hunting are 2005, 2004, 2007. Anything marked «too new» sits outside the ranking on purpose — complaints keep arriving for a decade after a car is sold, so a 2026 build would look flawless next to a ten-year-old one and comparing them would be dishonest.

When it starts to break

Not the calendar year the complaint was filed — the age of the car when it failed. That age decides who pays: inside the warranty the manufacturer does, outside it you do.

FIG.02·Mercedes-Benz CLK-Class — age at failure
Age at failureComplaintsRunning totalWarranty
0 years104.8%covered
1 year99.1%covered
2 years511.5%covered
3 years714.8%covered
4 years1120.1%you pay
5 years1929.2%you pay
6 years2038.8%you pay
7 years2852.2%you pay
8 years1961.2%you pay
9 years1769.4%you pay
10 years1476.1%you pay
11 years1583.3%you pay
12 years686.1%you pay
13 years1995.2%you pay
14 years798.6%you pay
15 years3100%you pay
ROWS 16·SOURCE NHTSA complaints with incident dates

Basic warranty on this car is 4 years / 50,000 miles. Only 14.8% of reported failures happen inside it — the remaining 85.2% come out of the owner's pocket. Powertrain cover (4 years / 50,000 miles) reaches further, but it only covers engine and transmission, and most complaints here are not either.

What actually fails — and at what age

Ordered by how often owners reported each system, with the age at which it typically goes. What waits further out is Fuel/propulsion System at 9 years — past every basic warranty, and the bill lands on whoever owns the car then.

FIG.03·Mercedes-Benz CLK-Class — what fails and when
SystemComplaintsTypical ageCrashFire
Fuel/propulsion System499 yrs
Electrical System437.2 yrs3
Air Bags317.9 yrs9
Seat Belts196.9 yrs1
Power Train186.2 yrs1
Seats146.4 yrs11
Engine1410.2 yrs1
Exterior Lighting139.3 yrs
ROWS 8·SOURCE NHTSA complaints
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How we measure it

Reliability scores usually arrive as a number out of five with no working shown. The Mercedes-Benz CLK-Class figure here comes out of 227 individual reports, and here is exactly how they were turned into a rate — two steps in it are arguable and you should be able to argue with them.

Rate, not total. Volume alone would decide the ranking, so we divide by the number of production runs — the distinct first-eleven-character VIN prefixes on record. The Mercedes-Benz CLK-Class alone splits into 163 runs carrying 227 complaints — 1.39 per run against 3.73 for the market.

Age, not year. Incident date minus model year gives the age at failure, which is what the warranty question turns on. It is why our «worst year» rankings exclude anything built in the last 6 years — those cars simply have not had time to break yet.

What this is not. Filing with a federal regulator takes effort, so what you see are faults someone judged serious — not scratched paint, not running costs, not how nice the car is to live with. For the Mercedes-Benz CLK-Class the file runs from 2002 to 2009, so the older years carry a full life of reports and the newest carry almost none.

Frequently asked questions

Is the Mercedes-Benz CLK-Class reliable?

It draws 1.39 complaints per production run against 3.73 for the average car, so better than typical. Failures cluster around 7 years of age.

What are the best and worst years for the CLK-Class?

Worst is 2006 at 1.54 complaints per run; best is 2009 at 1. Years newer than 6 are excluded — they have not had time to accumulate complaints.

How long does a CLK-Class last?

Complaints reach their halfway point at 7 years. That is when faults start being reported in volume, not when the car stops — but it is the point at which ownership starts costing money.

Will the warranty cover it?

Basic cover is 4 years / 50,000 miles, and 14.8% of reported failures fall inside it. The rest are yours.

What fails most often?

Fuel/propulsion System with 49 complaints, typically at 9 years of age.

Complaint records from NHTSA, grouped by VIN production run (characters 1–11). Rates, age-at-failure and warranty coverage computed by ForCar. Model years newer than 6 years are excluded from rankings — complaints accumulate for a decade. Last updated Sep 2026. — ForCar Reviewed by , founder of ForCar.
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