Mercedes Benz SLK MOT failures and reliability

In 2023 the Mercedes Benz SLK took 59,368 MOT tests in Britain and passed 73% of them first time, close to the national average of 71% for all cars. The figures below come from the DVSA's record of every test, so they show what testers actually found on these cars rather than what owners report.

MOT tests in 2023: 59,368
First-time pass rate: 73%
All cars: 71%

What the SLK fails on

Share of tests with at least one failure in each area, against the figure for all cars.

Suspension11.0% (all cars 9.0%)
Lights and electrics8.6% (all cars 11.3%)
Tyres6.3% (all cars 6.4%)
Brakes6.0% (all cars 6.8%)
Visibility3.3% (all cars 4.8%)
Exhaust and emissions2.5% (all cars 3.1%)
Body and structure1.5% (all cars 3.5%)
Seat belts and airbags1.2% (all cars 1.0%)

Most common failure items

Share of tests on which each item was recorded.

Coil spring: fractured or broken 5.1%
Suspension arms, ball joint: ball joint excessively worn 2.4%
Tread depth: tread depth below requirements of 1.6mm 2.3%
Tyres, condition: has ply or cords exposed 1.7%
Rigid brake pipes: excessively corroded 1.7%
Malfunction indicator lamp: inoperative or indicates a malfunction 1.6%
Stop lamp: not working 1.5%
Position lamp: not working 1.4%

Most common advisories

Tread depth: worn close to legal limit/worn on edge 16.2%
Rigid brake pipes: corroded, covered in grease or other material 11.1%
Tyres, condition: slightly damaged/cracking or perishing 7.7%
Brake discs: worn, pitted or scored, but not seriously weakened 7.4%
Brake pads: wearing thin 5.1%
Wheel bearings: has slight play 4.5%
Suspension arms, pins and bushes: pin or bush worn but not resulting in excessive movement 3.4%
Engine oil leaks: leak, but not excessive 3.1%

Pass rate by year of registration

Older cars fail more often whatever the model, so compare a car with others of the same age.

First registered	Tests	Pass rate
1997	794	68%
1998	1,164	69%
1999	1,614	68%
2000	2,049	69%
2001	2,379	69%
2002	2,078	70%
2003	1,894	65%
2004	3,231	65%
2005	5,012	67%
2006	3,831	68%
2007	3,568	68%
2008	3,265	69%
2009	2,516	68%
2010	2,099	71%
2011	2,555	77%
2012	5,580	77%
2013	4,644	77%
2014	4,920	80%
2015	4,858	83%
2016	1,265	87%

Typical mileage by age

Average odometer reading at the MOT, by the car's age in years at the test.

Age at test	Average mileage
7 years	37,741 miles
8 years	43,449 miles
9 years	50,453 miles
10 years	57,992 miles
11 years	59,681 miles
12 years	56,827 miles
13 years	62,924 miles
14 years	66,158 miles
15 years	72,067 miles
16 years	73,167 miles
17 years	77,212 miles
18 years	80,177 miles
19 years	82,184 miles
20 years	83,522 miles

Check a particular SLK

Model figures tell you what to look out for. To see one car's own MOT history, mileage and tax, enter its registration.

Other Mercedes Benz models

Source: Department for Transport, Anonymised MOT tests and results, 2023, cars and light vans, normal tests only. Pass rates are first-time passes; a pass after repair at the test station counts as a fail. Contains public sector information licensed under the Open Government Licence v3.0.