How do I read my tyre size? +
Your tyre size is printed on the sidewall in a format like 205/55R16 91V. The first number (205) is the width in millimetres, the second (55) is the aspect ratio as a percentage of the width, R means radial construction, and 16 is the wheel diameter in inches. The number after (91) is the load index and the letter (V) is the speed rating. Your vehicle handbook and the sticker inside the driver's door frame show the correct size for your car.
What does the TPMS warning light mean? +
The TPMS (Tyre Pressure Monitoring System) warning light indicates that one or more of your tyres has dropped below the recommended pressure. This could be caused by a slow puncture, a change in temperature, or simply natural air loss over time. Do not ignore it — under-inflated tyres increase braking distances and can overheat at speed. Check your pressures at the nearest petrol station or call a mobile tyre fitter.
Is it safe to drive on a slow puncture to reach a tyre fitter? +
If the tyre is only slightly low and you can maintain safe control of the vehicle, you can drive a short distance at reduced speed — no more than a few miles at 20–30mph. Check the tyre regularly as you drive. If the tyre is visibly flat, the sidewall is bulging, or the car feels unstable, do not drive at all. Call a mobile tyre fitter to come to your location instead.
Can a tyre blowout be repaired or does it need replacing? +
A tyre that has suffered a blowout almost always needs replacing. The internal structure of the tyre is usually destroyed by the sudden loss of pressure and the impact damage that follows. Even if the tyre appears intact, the sidewall and carcass will have been compromised. A tyre fitter can inspect it, but in the vast majority of cases a new tyre is the only safe option.
How old can tyres be before they need replacing? +
Even if the tread looks fine, tyres degrade over time as the rubber compound hardens and loses grip. Most manufacturers recommend replacing tyres after 5 years of use, and no tyre should remain in service for more than 10 years from the date of manufacture. You can check the age using the DOT code on the sidewall — the last four digits show the week and year of manufacture (e.g. 2319 means week 23 of 2019).
What are run-flat tyres and can any fitter work on them? +
Run-flat tyres have reinforced sidewalls that support the weight of the car even with no air pressure, allowing you to drive up to 50 miles at 30mph after a puncture. They require specialist fitting equipment and a TPMS reset after replacement. Not all garages can work on run-flat tyres, but most professional mobile fitters and tyre centres are fully equipped. Run-flat tyres are typically 20–40% more expensive than standard equivalents.