85.1%
Mercedes-Benz SLC
Mercedes-Benz SLC MOT pass rate and common problems
The Mercedes-Benz SLC passed 85.1% of its initial MOT tests in 2025, 12.8 percentage points above the 72.3% UK average. The item testers recorded most often was condition has ply or cords exposed.
Checking a specific car? Its own results, advisories and recorded mileages are in a free MOT history check.
How the SLC compares
Initial MOT tests in 2025, retests excluded. A car that failed and was repaired at the test station counts as a fail.
77.1%
Mercedes-Benz average
72.3%
UK average, all cars
The SLC runs 8 points ahead of the Mercedes-Benz average. It is 9th of the 35 Mercedes-Benz models in the data. The average SLC arrived at its test 7.6 years old with 36,347 miles recorded.
A pass rate records whether cars met the roadworthiness standard on test day. It is not a reliability score, and part of any gap reflects how old the tested cars were.
SLC MOT pass rate by age
The same 2025 tests split by the car's age at test.
Mercedes-Benz SLC cars aged 3 to 5 years passed 89.2% of MOT tests. For cars aged 6 to 10 years that fell to 84.4%, a drop of 4.8 percentage points.
| Age at test | Tests | Pass rate | vs UK average |
|---|---|---|---|
| 3 to 5 years | 1,447 | 89.2% | 16.9 pts above |
| 6 to 10 years | 7,527 | 84.4% | 12.1 pts above |
| 11 years and over (small sample) | 7 | 42.9% | 29.4 pts below |
That is a smaller decline than most cars show. The UK average of 72.3% covers cars of every age, so compare like with like.
Where SLC failures cluster
Every failure item recorded on Mercedes-Benz SLC cars in 2025, grouped into the DVSA's test areas.
Tyres and suspension together account for 64.4% of recorded failure items. These are recorded failures across the model, not faults every car has.
The 10 most common SLC MOT failures
Specific items recorded on Mercedes-Benz SLC cars that failed their 2025 MOT, as a share of all recorded failure items.
Together these 10 items make up 63.7% of everything testers recorded against failed Mercedes-Benz SLC cars. The rest is spread across many smaller items, and one failed test often records several at once.
What to look at on a SLC
The recorded failures above, grouped by area, biggest first.
1
Tyres
Recorded most often: condition has ply or cords exposed, condition has a cut in excess of the requirements deep enough to reach the ply or cords, tread depth below requirements of 1.6mm and condition has a tear, caused by separation or partial failure of its structure. 33.3% of failure items.
2
Suspension
Recorded most often: coil spring fractured or broken, ball joint excessively worn, ball joint dust cover no longer prevents the ingress of dirt and linkage ball joint dust cover ball joint dust cover no longer prevents the ingress of dirt. 23.3% of failure items.
3
Noise, emissions and leaks
Recorded most often: malfunction indicator lamp inoperative or indicates a malfunction. 4% of failure items.
4
Brakes
Recorded most often: anti-lock braking system warning lamp indicates an abs fault. 3.1% of failure items.
The car's own MOT history matters more than any model average. A free MOT history check shows whether a specific SLC has failed on these items before, or had them noted as advisories. Buying one? See the used Mercedes-Benz SLC buying guide.
Already found one?
Check its finance, write-off, theft, mileage and keeper history with a £15 vehicle history report.
Mercedes-Benz SLC MOT FAQs
What is the Mercedes-Benz SLC MOT pass rate?
85.1% of Mercedes-Benz SLC cars passed their initial MOT first time in 2025, from 8,981 tests. That is 12.8 percentage points above the 72.3% average for all cars, and ranks 119th of 575 models.
What does a Mercedes-Benz SLC most commonly fail its MOT on?
The item testers recorded most often on Mercedes-Benz SLC cars failing their 2025 MOT was condition has ply or cords exposed, on 12.6% of failure items. Next were condition has a cut in excess of the requirements deep enough to reach the ply or cords (9.7%) and coil spring fractured or broken (9%).
Which area causes the most Mercedes-Benz SLC MOT failures?
Across every recorded failure item, the largest area was tyres at 38.7%, followed by suspension at 25.7%.
Do older Mercedes-Benz SLC cars fail their MOT more often?
Mercedes-Benz SLC cars aged 3 to 5 years passed 89.2% of MOT tests in 2025, against 84.4% for cars aged 6 to 10 years.
Does this mean every Mercedes-Benz SLC has these problems?
No. These are the items testers recorded across every Mercedes-Benz SLC that failed in 2025. They show where the model most often needs attention, not the condition of any individual car.
How do I see a specific Mercedes-Benz SLC's MOT history?
Enter its registration on the free Carpeep MOT history check to see that car's own test results, failures, advisories and recorded mileages.
MOT figures are aggregated from the DVSA MOT Anonymised data set for 2025: class 4 initial tests, retests excluded, with failure items from failed tests (advisories and minor defects excluded), licensed under the Open Government Licence v3.0. MOT results describe roadworthiness at test, not mechanical reliability.