Used-car checks
Should You Buy a Car With MOT Advisories?
An advisory isn’t the same as an MOT failure. It can describe ordinary wear that needs budgeting, or it can be the first visible part of costly work. The wording, repetition and present condition provide the context.
Don’t reject a car merely because an advisory appears. Identify the item, judge its likely urgency and cost, look for repetition and repair evidence, then inspect the car as it stands today.
What an advisory means
An advisory records a condition the tester considers worth monitoring or repairing even though it wasn’t, at that test, a defect serious enough to fail the vehicle. Minor defects can also be recorded on a pass. Dangerous and major defects produce a failure.
An advisory is a dated observation, not a quotation and not a guarantee of remaining life. It may have been repaired since, or it may have worsened; the condition in front of you matters more than historic wording alone.
Judge the context, age and mileage
Some wear is normal on an older or high-mileage car. A tyre approaching its limit on an inexpensive everyday car is different from structural corrosion on a valuable classic, and the same repair bill represents a different proportion of each vehicle’s value.
Read the wording carefully, note the date and mileage, then ask whether the vehicle has travelled 500 miles or 15,000 miles since. Use the old advisory to focus today’s inspection rather than treating it as the current diagnosis.
Common advisories and what they may mean
Tyres approaching limits
Four millimetres or more is generally good, around three millimetres is often acceptable and around two millimetres is getting low even where a tyre may still be legal. Check all four tyres across their full width for cracking, perishing, damage and uneven wear. Repeated inner-edge wear may justify an alignment or suspension investigation.
Brake discs and pads
Wear can be routine, but cost depends on the axle, parts and vehicle. Grinding, vibration, warning lights or a poor pedal require prompt attention.
Bushes, ball joints and dampers
Suspension wording ranges from early wear to meaningful play or leakage. Repetition, knocks, poor tyre wear or unstable road behaviour justify closer inspection.
Oil leaks
A light misting is different from an active leak reaching the ground or contaminating other components. Establish the source and likely repair rather than assuming every leak is trivial.
Exhaust deterioration
Surface corrosion may be monitor-only; a leak, insecure section or costly integrated component is different. Listen from cold and inspect safely.
Corrosion
Location matters. Cosmetic surface corrosion and deterioration near structural or prescribed areas aren’t equivalent. Progression over several tests deserves professional assessment.
Windscreen damage
Size and position affect importance. Check whether a chip has spread, whether it obstructs the driver’s view and whether repair or replacement is realistic.
Repeated advisories tell a stronger story
The same item appearing year after year can show that repair was deferred, that the condition remained within an acceptable monitoring range or that related components continue to wear. Repetition is more revealing than one isolated note because it shows a pattern of attention—or inattention.
If the advisory later disappears, ask for supporting evidence where the repair matters. A receipt or detailed invoice is stronger than assuming a different tester’s silence proves the work was completed.
What bothers me more than the advisory itself?
One ordinary wear item is rarely the whole story. Repetition, several related advisories, no repair evidence, poor current condition, a dismissive explanation or multiple expensive safety-critical items arriving together all deserve more attention.
Use the advisory to decide what to inspect and what questions to ask. The concern rises when the paper trail, the seller’s explanation and the present vehicle stop agreeing with each other.
Budget, inspect, ask for proof—or walk away?
Ordinary wear with a predictable cost, such as tyres or wipers, when the current condition is clear and the price allows for it.
Suspension wear, leaks, braking concerns, uneven tyres or deterioration whose extent can’t be judged from the MOT wording alone.
An expensive repeated item that has now disappeared, or work the seller says was completed recently.
Serious or progressive corrosion, safety-critical concerns, several costly unresolved items, or uncertainty that makes no sense against the vehicle’s value.
Walking away is a commercial judgement, not an automatic response to a phrase on a certificate. A specialist or cherished older car may justify investigation that would make little sense on an ordinary low-value vehicle.
The car in front of you is the final evidence
An MOT history helps you decide what to look at, but it doesn’t replace a viewing, test drive or professional inspection. Check the current tyres, brakes, suspension behaviour, warning lights, leaks, glass and corrosion. Compare what you find with the service and repair invoices.
Return to the complete MOT history guide, check tyre tread and condition, read vehicle history and mileage or continue with the Used Car Buying Guide.