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Bentley 4.5 liters vs Bentley Unknown: reliability comparison

MOT pass rates, common faults and mileage compared from real UK MOT data.

Bentley 4.5 liters
83%
MOT pass rate · 1 vehicles
Bentley Unknown
90%
MOT pass rate · 9,548 vehicles
Verdict: On MOT pass rate the Bentley 4.5 liters (83%) and Bentley Unknown (90%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.

Head to head

Measure Bentley 4.5 liters Bentley Unknown
MOT pass rate 83% 90% ✓
MOT failure rate 17% 10% ✓
Faults & advisories per test 1.7 0.9 ✓
Dangerous-fault share 0% ✓ 7%
Average mileage — 34,409 mi
Sample size (vehicles) 1 9,548

Most common faults

Bentley 4.5 liters

  1. Oil leak
  2. Steering system has slight free play detected at steering wheel (2.2.A.1a)
  3. Offside Ball joint has slight play (2.2.B.1f)
  4. Service brake: service brake efficiency only just met. It would appear that the braking system requires adjustment or repair. (3.7.C.1a)
  5. Nearside Front Axle king pin has slight play in pin and/or bush (2.5.A.3a)
  6. Nearside Front Leaf spring has slight side play at eye (shackle) (2.4.B.4)

Bentley Unknown

  1. COVID-19 6 MONTH EXTENSION
  2. Parking brake efficiency less than 50% of the required value (1.4.2 (a) (ii))
  3. Parking brake: efficiency below requirements (3.7.B.7)
  4. Windscreen washer provides insufficient washer liquid (8.2.3)
  5. Oil leak
  6. Offside Rear Tyre worn close to legal limit/worn on edge (5.2.3 (e))

Reliability FAQ

On MOT pass rate the Bentley 4.5 liters (83%) and Bentley Unknown (90%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.

Full Bentley 4.5 liters report Full Bentley 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.