Flat Spots on Tyres: Causes, Damage and Whether They Fix Themselves

You start a car that has been sitting for a while, and the first few kilometres feel like driving on square wheels — a rhythmic thumping vibration that eases as you get going. That is almost always a flat spot. The important question is whether it will settle on its own or whether the tyre is permanently damaged. The answer depends entirely on what caused it.

What causes a flat spot on a tyre?

Flat-spotting happens when a stationary tyre is held in one position under the weight of the car. The contact patch — the part touching the ground — is squashed flat, and if the tyre stays there long enough the rubber and internal structure temporarily hold that shape instead of springing back to round. Cold weather makes it worse, because cool rubber is stiffer and sets more readily, which is why a car parked overnight through a cold snap can thump the next morning.

The main contributors are how long the car sits, the temperature, and the tyre pressure. An underinflated or overloaded tyre flat-spots faster and more severely, because more of the sidewall is deformed. A separate and more serious kind of flat spot comes from hard braking or a wheel lock-up, where a skid grinds a genuine bald patch into the tread — that is abrasion damage, not a shape the tyre can recover.

Temporary vs permanent flat spots: what’s the difference?

Temporary flat-spotting is the common one. After a few days or weeks parked you may feel a vibration for the first few minutes, but once the tyres reach operating temperature and regain their round shape it disappears. Semi-permanent flat-spotting develops after a month or more of storage, especially in heat with low pressure, and normal driving will not remedy it. A flat spot ground in by a skid is permanent from the moment it happens.

Do flat spots go away on their own?

Temporary ones do. The cure is simply to drive: as the tyre flexes and warms, the rubber relaxes back to round, usually within a few kilometres. Gentle driving for the first stretch helps. If the vibration is still there after 15–20 km of normal driving, or it comes and goes at highway speed, treat it as more than a simple flat spot. Persistent vibration around 100 km/h can also point to wheel balance or other faults — see our guide to vibration at 100 km/h to tell them apart.

How do you prevent flat spots?

If a car is going to sit, a little preparation goes a long way:

• Set pressures correctly first. Underinflation is the biggest accelerant. Follow the placard pressure, not the sidewall maximum, and never exceed the tyre’s maximum cold pressure. Some owners add a small amount of pressure before long-term storage — a common tip is a modest top-up above placard while parked, brought back to placard before driving.
• Move the car occasionally. Rolling it forward or back every couple of weeks changes which part of the tyre bears the load. Even a short drive helps.
• Check pressures regularly. Tyres lose air over time; a car left for months can be well down. See how often you should check tyre pressures.
• Take the load off for very long storage. For months-long lay-ups, supporting the car so the tyres carry less weight prevents setting. Our guide to storing a car long-term without flat-spotting covers this in detail, and if your car simply sits unused most of the week there are tyre choices that cope better.

Frequently asked questions

How long does a car have to sit to flat-spot a tyre?

Temporary flat spots can form in just a few days of parking, particularly in cold weather or with low pressure. Setting that resists normal driving generally needs a month or more of standing.

Will a flat-spotted tyre damage my car?

A temporary flat spot mostly causes an annoying vibration that clears quickly. A permanent flat spot creates ongoing vibration that can stress wheel bearings and suspension over time, so have it checked rather than living with it.

Can a flat spot be fixed without replacing the tyre?

Temporary ones fix themselves by driving. A skid-ground flat spot cannot be repaired. Some semi-permanent cases can be assessed by a tyre specialist, but replacement is often the outcome.

Does higher tyre pressure prevent flat spots?

Correct-to-slightly-higher pressure resists flat-spotting because it keeps the tyre rounder under load. Never exceed the maximum cold pressure marked on the sidewall, and return to placard pressure before driving.

Guidance here is general. Follow your vehicle’s placard and manufacturer advice, and have persistent vibration inspected by a tyre professional. Legal minimum tread depth in Australia is 1.5 mm in all principal grooves.

Sources: Continental Tyres – Flat-spotting; Michelin – Tire Flat-Spotting causes and prevention.