You’ve checked the mileage, scanned the bodywork, and flicked through the service history, the car looks right on paper, but according to the technicians who inspect these cars every day, that’s where most buyers stop – and exactly where problems could hide.
A survey of 55 dealership technicians, master technicians, and aftersales managers across Vertu’s UK network found that 73% believe turning the radio off and driving over different road surfaces to listen for mechanical noises is the single most important used car test drive check, and one of the checks buyers are most likely to skip.
The finding comes from Vertu Quarterly Aftersales Survey, which asked technicians to identify the checks most used car buyers overlook.
Beyond the test drive, over half (53%) said cheap, non-original parts spotted under the bonnet are the clearest sign of a car with a troubled history. The brand of tyres fitted, and the smell of the interior (both 16.4%) were also flagged as overlooked indicators.
Matt Salisbury, PR Lead at Vertu, said, “The feedback from our technicians showed is that buyers tend to focus on the things they can research from home: mileage, service history, MOT records.
“Those are important, but they only tell you what’s been documented. What they can’t tell you is how the car actually sounds when it’s accelerating, braking, and going over bumps, whether someone’s patched it up with the cheapest parts available, or whether there’s damp hiding under the carpets.
“A ten-minute test drive with the radio off and five minutes looking under the bonnet will often tell you more than an hour spent reading paperwork.”
With searches for ‘what to look for when buying a used car’ rising by 23% in the last three months, the experts at Vertu have outlined four checks that technicians rely on but most buyers overlook when on the forecourt.
Turn the radio off and listen for noises on different roads
Suspension defects are the second most common reason for MOT failure in the UK, accounting for 8.7% of all failures according to the DVSA[1]. Many of these faults produce audible warnings long before they show up visually, but most buyers never hear them because the radio is on.
Switch off the radio and air conditioning, drop the windows, and try to drive on at least three different surfaces: a smooth dual carriageway, a rough residential road, and over a couple of speed bumps. A steady hum that rises with speed can point to wear in the wheel’s moving parts. If you feel a knock over bumps, it could indicate a problem with the suspension. And, If you hear grinding when you brake, it means the brake pads or discs may need attention.
Open the bonnet and look for non-original parts
When a previous owner has cut costs on replacement parts, it rarely stops at one. Non-original components can wear faster and fit less precisely, but the real concern is the pattern. If the visible repairs were done cheaply, the hidden ones may have been too.
Open the bonnet and look at the visible components. Original parts typically carry the manufacturer’s branding or a recognised supplier’s logo. Warning signs include unbranded parts, components that look newer than their surroundings but differ in colour or finish, mismatched bolts, and cable ties or improvised fixings holding things together.
Check the brand and condition of all four tyres
Tyres can tell you a lot about how a car has been maintained. Budget rubber from lesser-known brands, or a different brand on each corner, may suggest that replacements were made at the lowest specification rather than as a set. It’s not always a concern on its own, but it’s worth factoring in alongside the overall condition of the car.
Check that all four match, as mismatched tyres suggest they were replaced one at a time at the lowest price. Wear on one side of the tyre points to alignment issues, while uneven, patchy wear across the surface can signal suspension problems. Check the DOT code on the sidewall (e.g., 2223 means week 22, 2023); tyres older than five years may need replacing regardless of tread.
Sit inside, close everything, and use your nose
Damp or musty smells can point to water ingress, failed seals, or previous flood damage, all of which lead to corrosion, mould, and electrical faults that are costly to fix. Stale smoke is almost impossible to remove from headlinings and seat foam. A strong air freshener should raise questions, not confidence.
Sit in the driver’s seat with the windows and doors closed and breathe in. Then start the car and turn the heating to full with the air recirculating. This pulls air through the ventilation system and can release trapped damp that isn’t detectable when the car is cold. Lift the floor mats and press the carpet underneath with your hand. If it feels damp, soft, or smells musty, there may be a leak or water leaking into the cabin that could lead to expensive electrical problems down the line.
Of course, when you buy a used car from an established dealership like Vertu, many of these checks are carried out for you as part of the preparation process, giving you peace of mind before you drive away.
