Triumph 2500s vs Triumph Unknown: reliability comparison
MOT pass rates, common faults and mileage compared from real UK MOT data.
Triumph 2500s
78%
MOT pass rate · 41 vehicles
Triumph Unknown
89%
MOT pass rate · 65,927 vehicles
More reliable
Verdict: On MOT pass rate, the Triumph Unknown is the more reliable of the two — 89% pass first time versus 78%. It's one signal among several; check the full breakdown below.
Head to head
| Measure | Triumph 2500s | Triumph Unknown |
|---|---|---|
| MOT pass rate | 78% | 89% ✓ |
| MOT failure rate | 22% | 11% ✓ |
| Faults & advisories per test | 1.5 | 0.6 ✓ |
| Dangerous-fault share | 0% ✓ | 2% |
| Average mileage | 65,447 mi | 16,601 mi |
| Sample size (vehicles) | 41 | 65,927 |
Most common faults
Triumph 2500s
- Oil leak
- Nearside Rear Brake pipe slightly corroded (3.6.B.2c)
- Parking brake: efficiency below requirements (3.7.B.7)
- Exhaust emissions carbon monoxide content excessive (7.3.B.1a)
- Nearside Front wheel bearing has slight play (2.5.A.3c)
- Offside Front wheel bearing has slight play (2.5.A.3c)
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 Unknown is the more reliable of the two — 89% pass first time versus 78%. It's one signal among several; check the full breakdown below.
Full Triumph 2500s 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.