Suspension arm ball joint at the MOT: which cars fail on it most
5.1% of failed initial MOT tests in 2025 recorded this defect: 471,377 of 9,185,328. By age, it was most common on vehicles 10 to 14 years old (6.4%) and least common on vehicles under 3 years old (1.0%).
It is one of the 10 most common MOT failures on 89 of the 332 car models we cover. Against vehicles of the same age, it was most common on the Mercedes-Benz EQC, the Tesla Model Y and the Mercedes-Benz GLC. On the Mercedes-Benz EQC, 12.5% of failed tests had it, against 1.1% for all vehicles of the same age.
The DVSA records it as “Suspension arm ball joint excessively worn”. A failed test can have several defects.
What the MOT checks
A ball joint on a suspension arm that is excessively worn.
The MOT inspection manual lists “A suspension pin, bush, joint or bearing excessively worn” as a major defect, so the vehicle fails.
Car models where it is most common
| # | Car | Share of failed tests | Against same age |
|---|---|---|---|
| 1 | Mercedes-Benz EQC2,010 failed tests | 12.5%252 tests | 11.9×all: 1.1% |
| 2 | Tesla Model Y5,417 failed tests | 7.4%401 tests | 8.4×all: 0.9% |
| 3 | Mercedes-Benz GLC11,486 failed tests | 20.5%2,356 tests | 7.6×all: 2.7% |
| 4 | Renault Zoe4,932 failed tests | 19.2%946 tests | 7.6×all: 2.5% |
| 5 | Nissan Leaf10,172 failed tests | 20.6%2,095 tests | 5.7×all: 3.6% |
| 6 | Nissan X-Trail26,279 failed tests | 23.0%6,054 tests | 4.7×all: 4.9% |
| 7 | Tesla Model 313,522 failed tests | 5.8%788 tests | 4.6×all: 1.3% |
| 8 | Mercedes-Benz S-Class2,067 failed tests | 20.2%418 tests | 4.3×all: 4.7% |
| 9 | Nissan Juke99,185 failed tests | 22.4%22,257 tests | 4.2×all: 5.4% |
| 10 | Nissan Pulsar6,101 failed tests | 20.7%1,265 tests | 4.1×all: 5.0% |
| 11 | Mercedes-Benz CLC3,277 failed tests | 25.1%824 tests | 3.9×all: 6.4% |
| 12 | Mercedes-Benz V-Class1,876 failed tests | 13.5%254 tests | 3.9×all: 3.4% |
| 13 | Mercedes-Benz CLK8,628 failed tests | 18.5%1,595 tests | 3.3×all: 5.5% |
| 14 | Mercedes-Benz C-Class90,099 failed tests | 16.9%15,245 tests | 3.2×all: 5.4% |
| 15 | Mazda 237,726 failed tests | 17.0%6,426 tests | 2.9×all: 5.8% |
Only models where this defect is one of their 10 most common MOT failures, with at least 50 failed tests, have a figure. So a model that isn't listed can still have it, just less often than its other faults. Vans, pick-ups and taxis are left out, as in our rankings. × is the model's share divided by the share for all vehicles of the same age.
How common it is by car age
- Under 3 years, first used 2023 to 20241.0% of failed tests, against 5.1% for all ages108 failed tests
- 3 to 5 years, first used 2020 to 20221.1% of failed tests, against 5.1% for all ages7,718 failed tests
- 6 to 9 years, first used 2016 to 20193.5% of failed tests, against 5.1% for all ages73,668 failed tests
- 10 to 14 years, first used 2011 to 20156.4% of failed tests, against 5.1% for all ages216,197 failed tests
- 15 to 19 years, first used 2006 to 20106.1% of failed tests, against 5.1% for all ages133,834 failed tests
- 20 years and over, first used 1985 to 20054.9% of failed tests, against 5.1% for all ages39,852 failed tests
All-vehicle figures cover vehicles first used from 1985 to 2024: 9,185,328 of the 9,193,164 failed initial tests in 2025.
How these figures are counted
These are failures recorded at initial MOT tests in 2025. Retests are not counted. A defect found on more than one wheel, lamp or joint at the same test counts once. "Same age" is the defect's share of failed tests for all vehicles first used in the same years, weighted by the model's own failed tests in each year.
An MOT checks safety and emissions on the day of the test. These figures show where a defect was recorded, not why, and not what a repair costs. Figures: DVSA anonymised MOT tests and results, 2025. Contains public sector information licensed under the Open Government Licence v3.0. What the MOT checks: MOT inspection manual: cars and passenger vehicles, GOV.UK, read 1 Nov 2026.
How we choose and rank these defectsOther suspension faults
- Coil spring8.6% of failed tests
- Suspension arm bush4.4% of failed tests
- Shock absorber leak3.1% of failed tests
- Anti-roll bar link cover2.7% of failed tests
- Anti-roll bar link joint2.3% of failed tests
- Suspension arm dust cover1.8% of failed tests
- Corroded suspension mount1.8% of failed tests
Share of all failed initial MOT tests in 2025.