How to Inspect Tyre Damage Before It Gets Serious

A tyre can look acceptable from the side of the car and still have damage that makes it unsafe at motorway speed. Knowing how to inspect tyre damage gives you a better chance of spotting a problem before it becomes a puncture, a blow-out or an expensive damaged wheel. It takes only a few minutes, but the check needs to cover more than tread depth.

Park on level ground, apply the handbrake and inspect tyres in good daylight where possible. If the vehicle has just been driven, avoid touching the brakes or wheel centre as these may be hot. A torch, tyre-pressure gauge and a 20p coin are useful, but your eyes and hands will identify many of the most serious warning signs.

Start with the whole tyre, not just the tread

Walk around the vehicle and look at every tyre from the front, side and rear. Turn the steering wheel to full lock when checking the front tyres, with the engine running only if your vehicle requires it for power steering. This exposes more of the inner and outer shoulders, where damage and unusual wear are often missed.

Look for obvious deflation first. A tyre that is visibly lower than the others may have a puncture, a leaking valve or damage to the wheel rim. Do not assume it is fine because it still holds enough air to drive on. Slow leaks can become sudden failures once the tyre heats up on a longer journey.

Then run your hand carefully across the tread surface and sidewall. You are looking for changes in shape, sharp objects and rough areas. Keep your fingers clear of anything embedded in the tyre. Pulling out a nail or screw can turn a manageable slow puncture into a completely flat tyre.

How to inspect tyre damage in the tread

The tread is designed to take everyday contact with the road, but it is not invincible. Small cuts, stones and surface scuffs are common. The question is whether the damage has gone deep enough to compromise the tyre’s structure.

Check each groove for nails, screws, glass, flints and pieces of metal. If an object is lodged in the tread, note its position and arrange an inspection. A puncture in the central tread area may sometimes be repairable, depending on its size, angle and the tyre’s internal condition. A puncture close to the shoulder, however, is usually not suitable for repair.

Pay close attention to cuts. A shallow split in the outer rubber may not always require replacement, but a cut deep enough to reveal fabric, steel cords or any material beneath the rubber means the tyre must be replaced. Cords can appear as fine threads or metallic strands. Never drive on a tyre with exposed cords, even for a short local trip.

Also inspect the tread blocks for chunks missing or areas that look torn. This can happen after striking debris, driving over a sharp kerb edge or using a tyre that has been run underinflated. A damaged tread block affects grip and may indicate internal damage that is not visible externally.

Check tread depth and wear indicators

UK legal minimum tread depth for cars is 1.6mm across the central three-quarters of the tread, around the full circumference. The 20p test is a useful quick check: place the coin into a main tread groove and, if the outer band is obscured, the tread is generally above the legal minimum. It is still only a guide, not a precise measurement.

Most tyres also have tread-wear indicators inside the grooves. These are small raised bars. When the tread surface is level with those bars, replacement is due. For wet-weather confidence, many drivers choose to replace tyres before they reach the legal limit, particularly ahead of winter or high-mileage motorway use.

Uneven wear matters as much as remaining depth. Examine the full width of the tread rather than one convenient spot. Common patterns include:

• Wear on both outer edges, often linked to persistent underinflation.
• Wear down the centre, commonly caused by overinflation.
• Wear on one shoulder, which may point to alignment, suspension or wheel-fitment issues.
• Cupped, scalloped or patchy wear, which can be associated with worn suspension components or wheel imbalance.

Correcting pressure alone will not restore worn rubber. If a tyre has worn unevenly, it is worth having the alignment, suspension and wheel balance assessed before fitting replacements. Otherwise, the same issue can shorten the life of the next set.

Treat sidewall damage seriously

The sidewall flexes constantly as the tyre rotates. It has far less protection than the tread, which is why sidewall damage deserves a cautious approach.

Look for cuts, splits, deep scuffs and cracking. Minor surface marks from brushing a kerb are often cosmetic, but a gouge that is deep, open or showing cords is not. A workshop should inspect any damage you are unsure about, especially on low-profile tyres where the sidewall is shorter and impacts can be more severe.

A bulge or bubble is an immediate stop-driving warning. It usually means the internal cords have been damaged, often after hitting a pothole or kerb. The outer rubber may remain intact, but the tyre no longer has its intended structural strength. It cannot be safely repaired and should be replaced before the vehicle is driven again.

Fine cracking can develop as tyres age, particularly on vehicles that do low mileage, are stored outside or spend long periods stationary. Light surface crazing does not always mean imminent failure, but deeper cracks around the sidewall, bead or tread grooves warrant a professional inspection. Check the tyre’s age code too. The final four digits of the DOT marking show the week and year of manufacture. Age is only one factor, but older tyres should be assessed carefully even when their tread looks healthy.

Check the bead, valve and wheel rim

Not every air leak is caused by a puncture. The bead is the area where the tyre seals against the wheel. Corrosion on an alloy wheel, kerb damage, a distorted rim or old sealing residue can all allow air to escape gradually.

Inspect the wheel rim for dents, cracks, severe kerbing and flaking corrosion around the tyre edge. A cracked wheel is unsafe, while a bent rim can cause vibration, poor sealing and uneven tyre wear. Alloy wheel refurbishment can resolve some cosmetic corrosion and kerb damage, but structural cracks and significant distortion need specialist assessment before any repair is considered.

Check that valve caps are fitted and that valve stems are not split, perished or bent. The cap helps keep dirt and moisture out of the valve, although it is not the primary air seal. If a tyre repeatedly loses pressure without an obvious puncture, the valve and bead area should be tested by a tyre professional.

Know when to stop driving

Some issues need a booking soon. Others mean the vehicle should stay parked until the tyre is replaced or inspected. Do not drive if you find a sidewall bulge, exposed cords, a deep sidewall cut, a tyre that has come off the bead, a visible wheel crack or a tyre that has been driven flat.

Driving on a flat or seriously underinflated tyre can damage its internal structure in a short distance. Even if it reinflates and appears normal, it may no longer be safe to repair. Run-flat tyres need the same caution: their reinforced construction can make a puncture less obvious, and they should be inspected after any low-pressure warning or suspected pressure loss.

If there is a nail in the central tread and the tyre is holding pressure, avoid high speeds and unnecessary journeys. Check the pressure, follow the vehicle manufacturer’s guidance and arrange a prompt professional assessment. Do not use aerosol sealant unless it is the appropriate emergency solution for your vehicle and you understand its limitations. It can complicate repair and does not fix structural damage.

Make tyre checks part of normal maintenance

A monthly inspection, plus a check before a long journey, is a sensible routine. Check pressures when tyres are cold and use the pressure specified for your vehicle and load, usually found in the handbook, fuel flap or driver’s door area. Do not rely on the maximum pressure printed on the tyre sidewall.

It is also worth inspecting tyres after a hard pothole strike, a kerb impact, off-road use or any sudden change in handling. Vibration through the steering wheel, a pull to one side, repeated pressure loss or a new thumping noise can all point to a tyre or wheel problem.

When damage is unclear, do not guess. A hands-on inspection can establish whether a tyre is safe, repairable or due for replacement, while also checking the wheel, valve and fitment. For Dorset drivers, The Tyre Barn can assess the condition of your tyres and wheels at its Wimborne fitting centre, helping you make the right call before a small defect becomes a roadside problem.