MOT failures by make
Isuzu MOT failures for “Rbt (sp): efficiency below requirements”
Isuzu cars failed their MOT on “Rbt (sp): efficiency below requirements” in 1.58% of 88,097 tests in 2023–2024 (1,392 tests) — 1.5 times as often as comparable cars of the same age, mileage and fuel, which would have failed on it in about 1.05% of tests. It is the number 14 most common failure item on Isuzus.
Data to 2024-12-30 · Page updated 2026-09-28 · Publisher: 73 Auto
- Isuzu tests failing on it
- 1.58%
- 1,392 of 88,097 tests, 2023–2024
- Comparable cars
- 1.05%
- national rate at the same age, mileage and fuel
- Observed ÷ expected
- 1.50×
- 73 Auto analysis · rank #14 for Isuzu
How unusual this is for the make
Across all MOT failures, Isuzus fail 1.13× as often as comparable cars. On this item the gap is 1.33× wider than that overall level, so it is a genuine Isuzu pattern rather than a reflection of how often the make fails in general. It is a major defect in the brakes part of the test. Nationally it appears on 1.11% of MOT tests.
Isuzu models and “Rbt (sp): efficiency below requirements”
The Isuzu D-Max is most affected (2.37× comparable cars); the Isuzu Rodeo least (0.86×). Not every model follows the make: the pattern is concentrated in some models. Model rows compare with cars of the same age and fuel.
| Model | Tests | Failed on it | vs similar cars |
|---|---|---|---|
| Isuzu D-Max | 66,975 | 1.30% | 2.37× |
| Isuzu Rodeo | 10,650 | 2.38% | 0.86× |
By age at test
The difference is largest at 5-6 years old: 1.06% of Isuzu tests against 0.30% for comparable cars.
| Age (years) | Isuzu tests | Isuzu | Comparable cars |
|---|---|---|---|
| 3-4 | 13,125 | 0.36% | 0.18% |
| 5-6 | 15,989 | 1.06% | 0.30% |
| 7-8 | 17,801 | 1.56% | 0.62% |
| 9-10 | 13,260 | 2.19% | 1.12% |
| 11-12 | 7,325 | 2.87% | 1.77% |
| 13-15 | 5,207 | 2.46% | 2.43% |
| 16+ | 11,348 | 2.32% | 2.93% |
Other Isuzu MOT faults that stand out
- Shock absorbers: has an excessively worn bush · 27.75× comparable cars
- Rear fog lamp: not working · 7.80× comparable cars
- Exhaust system: has a major leak of exhaust gases · 7.01× comparable cars
- Wheel bearings: has excessive play · 10.13× comparable cars
- Rigid brake pipes: excessively corroded · 3.92× comparable cars
- Position lamp: not working · 1.74× comparable cars
- Ball joint: ball joint excessively worn · 1.82× comparable cars
- Wipers: does not clear the windscreen effectively · 1.55× comparable cars
- Brake pads: less than 1.5 mm thick · 0.67× comparable cars
Limitations
Official data: DVSA's anonymised MOT results (2023–2024), class 4 initial tests, cars at least 2.5 years old. 73 Auto analysis: the comparison rate applies the national rate of this item for each test's own age, mileage band and fuel to the Isuzu tests. An MOT result reflects maintenance, mileage and how a car is used as well as its design, so this is not a measure of which make is most reliable. The wording of the defect is DVSA's.
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UK number plate or 17-character VIN
Where these figures come from
- Anonymised MOT tests and results (2023 and 2024) — Driver and Vehicle Standards Agency (DVSA). Open Government Licence v3.0.
Figures labelled as 73 Auto estimates are our own analysis of these sources, set out in the methodology and data sources. To report a factual error, see corrections.