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MOT fail rates

Mercedes-Benz Slk MOT fail rate by age

How often the Mercedes-Benz Slk fails its MOT at each age, compared with all cars of the same age, and what it fails on. From 227,766 DVSA MOT tests taken 2022 to 2025.

MOT data updated

At 10 years, the most tested age

MOT fail rate at age 10 (n=20,060)21.7%
All cars at 10 years (n=9,049,507)30.3%
Median mileage at test52,192
All cars, median mileage75,043

70 of 309 model groups with enough tests fail less often at 10 years.

What stands out

  • At 6 years the Mercedes-Benz Slk fails 11.6% of MOTs (1,253 tests), 6.2 points below the 17.8% for all cars that age. At 25 years it fails 30.3% (4,986 tests), 6.0 points below the 36.3% average.
  • The gap is widest at 13 years: 11.7 points below all cars.
  • Its most common structural or mechanical fail item at 10 years: Coil spring broken, at 5 per 100 MOTs.

MOT fail rate by age

6 years 25 years 47.6%

Solid line: this model. Dashed line: all cars at the same age.

Mercedes-Benz Slk: share of MOT tests that failed, by age, against all cars. Ages with fewer than 1,000 tests are not shown.
AgeMOT fail rateTests (n)All carsDifferenceMedian mileage
6 years11.6%1,25317.8%−6.2 pts30,977 miles
7 years14.4%6,17820.6%−6.2 pts36,626 miles
8 years16.9%11,01023.8%−6.8 pts42,025 miles
9 years20.0%15,74027.1%−7.1 pts47,610 miles
10 years21.7%20,06030.3%−8.6 pts52,192 miles
11 years23.3%17,54933.3%−9.9 pts56,045 miles
12 years25.3%14,76136.0%−10.7 pts59,332 miles
13 years26.5%12,71138.3%−11.7 pts61,150 miles
14 years29.2%10,40140.3%−11.1 pts63,244 miles
15 years30.3%11,49641.6%−11.3 pts67,412 miles
16 years31.6%13,13342.6%−11.0 pts71,115 miles
17 years31.5%15,71043.1%−11.6 pts74,869 miles
18 years33.0%15,59743.3%−10.3 pts77,599 miles
19 years32.8%13,64943.2%−10.4 pts79,781 miles
20 years32.8%11,76042.8%−10.0 pts81,231 miles
21 years31.9%9,25342.1%−10.2 pts83,417 miles
22 years30.5%8,19741.0%−10.5 pts85,450 miles
23 years30.4%7,65839.6%−9.3 pts86,621 miles
24 years30.8%6,66437.8%−7.0 pts87,060 miles
25 years30.3%4,98636.3%−6.0 pts87,523 miles

Most common fail items at 10 years

Split into structural or mechanical items and wear items. Wear items (tyres, brake pads, wipers, bulbs) say more about upkeep than about the design.

Structural and mechanical

Fail itemPer 100 MOTs
Coil spring broken Major5
Linkage ball joint dust cover: ball joint dust cover no longer prevents the ingress of dirt Major2
Suspension ball joint worn Major1.3
Anti-lock braking system: warning lamp indicates an ABS fault Major1.2
Rigid brake pipes: excessively corroded Major0.9

Out of 20,060 MOTs. A test with two faults counts twice.

Wear and upkeep

Fail itemPer 100 MOTs
Tyre tread below 1.6 mm Dangerous3.6
Tyre with cords exposed Dangerous2.8
Tyre condition: has a cut in excess of the requirements deep enough to reach the ply or cords Major1.8
Headlamp aim: too low Major1.1
Tyre condition: has a tear, caused by separation or partial failure of its structure Dangerous1

Out of 20,060 MOTs. A test with two faults counts twice.

Other models at 10 years

ModelMOT fail rateTests (n)All cars
Mercedes-Benz C-Class25.2%115,49830.3%
Mercedes-Benz E-Class24.3%76,96630.3%
Mercedes-Benz A-Class28.5%72,28730.3%

MOT fail rate by first-use year

Each year has its own page: the fail rate for cars first used that year at each MOT from 2022 to 2025 with at least 1,000 tests, the most common faults at that age, and the car tax and ULEZ rules for that year.

First-use year data updated .

Latest MOT age with at least 1,000 tests for each first-use year.
First usedAge at testMOT fail rateTests (n)All cars
199825 years in 202330.4%1,17436.3%
199925 years in 202430.3%1,38036.3%
200025 years in 202530.2%1,52536.3%
200124 years in 202528.9%1,86337.8%
200223 years in 202528.8%1,64539.6%
200322 years in 202531.7%1,53641.0%
200421 years in 202533.4%2,79242.1%
200520 years in 202531.7%4,47842.8%
200619 years in 202532.7%3,50743.2%
200718 years in 202532.4%3,41743.3%
200817 years in 202531.9%3,13743.1%
200916 years in 202530.6%2,46142.6%
201015 years in 202529.2%2,04941.6%
201114 years in 202524.7%2,49740.3%
201213 years in 202526.2%5,52738.3%
201312 years in 202525.7%4,51036.0%
201411 years in 202523.5%4,80833.3%
201510 years in 202519.9%4,86830.3%
20169 years in 202517.6%1,25327.1%

More on the Mercedes-Benz Slk

Read this with care. A fail rate is not a measure of build quality. How far cars are driven, how they are used and how well owners maintain them all change it, and wear items such as tyres and brake pads are common fails. Compare a model only with cars of the same age. Methodology and limits.

Looking at one Mercedes-Benz Slk?

These are figures for the model, not for one car. The VetTheCar Buying Report looks at a single car: its MOT tests, defects, advisories and mileage readings.

See an example report Browse the car tools

Source

Contains public sector information licensed under the Open Government Licence v3.0. Source: DVSA anonymised MOT test data, class 4 normal MOT tests, 2022 to 2025. MOT data updated 22 September 2026.

Not affiliated with or endorsed by DVSA. How we calculate these figures · Data sources