What to do if you get a flat tire

The first thirty seconds

• Do not brake sharply — a blowout makes the car pull, and hard braking amplifies it.
• Grip the wheel firmly and let the vehicle slow gradually.
• Signal and move to the right, aiming for a flat, level surface away from live lanes.
• Put the hazard lights on as soon as you begin slowing.
• Stop somewhere with room to work — a parking lot beats a narrow shoulder.

Should you change it yourself?

Only if the location is safe. A flat, level surface well clear of traffic with room to kneel on the far side of the vehicle is fine. A narrow shoulder with cars passing at speed a metre away is not — that is where roadside changes turn into serious incidents.

You also need the equipment: a usable spare, a jack, a wrench, and the wheel lock key if the vehicle has locking nuts. Check the trunk before committing to the plan.

If the car has no spare

Many recent vehicles carry a sealant and inflator kit instead of a spare wheel. Sealant can get you moving after a small puncture in the tread, but it does nothing for a sidewall cut or a blowout.

Without a usable spare there is no roadside change available. You will need a mobile tire supplier or transport to a tire shop. In a rental, call the rental company first — they often arrange it or swap the vehicle.

After the spare is on

• Check the pressure in the spare — spares often sit for years and lose air.
• If it is a compact spare, observe the speed and distance limits on its sticker.
• Get to a tire shop promptly; you now have no backup.
• Have the flat inspected — a tread puncture may be repairable, a sidewall cut is not.