Triumph Herald convertable vs Triumph Unknown: reliability comparison
MOT pass rates, common faults and mileage compared from real UK MOT data.
Triumph Herald convertable
75%
MOT pass rate · 8 vehicles
Triumph Unknown
89%
MOT pass rate · 65,927 vehicles
Verdict: On MOT pass rate the Triumph Herald convertable (75%) and Triumph Unknown (89%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.
Head to head
| Measure | Triumph Herald convertable | Triumph Unknown |
|---|---|---|
| MOT pass rate | 75% | 89% ✓ |
| MOT failure rate | 25% | 11% ✓ |
| Faults & advisories per test | 1.8 | 0.6 ✓ |
| Dangerous-fault share | 0% ✓ | 2% |
| Average mileage | 66,306 mi | 16,601 mi |
| Sample size (vehicles) | 8 | 65,927 |
Most common faults
Triumph Herald convertable
- Registration plate lamp not working (1.1.C.1d)
- Oil leak
- Oil leak
- Front Windscreen washer provides insufficient washer liquid (8.2.3)
- Offside Front wheel bearing has slight play (2.5.A.3c)
- Windscreen washer provides insufficient washer liquid (8.2.3)
Triumph Unknown
- Exhaust noisy (8.1.1 (a))
- Exhaust noisy (7.1.2)
- Front Roller brake test indicates slight fluctuation of brake effort (3.3.A1d)
- COVID-19 6 MONTH EXTENSION
- Rear Tyre worn close to the legal limit (5.2.3 (e))
- Steering headbearing has slight free play (2.2.2)
Reliability FAQ
On MOT pass rate the Triumph Herald convertable (75%) and Triumph Unknown (89%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.
Full Triumph Herald convertable report Full Triumph Unknown report Most reliable cars
Pass rates are computed over completed (pass/fail) MOT tests. Reliability also depends on age, mileage and upkeep — see each model's page for the full picture.