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.
Do I need to replace all four tyres at the same time? +
No, you do not need to replace all four tyres at once unless they are all worn. It is best practice to replace tyres in pairs (both fronts or both rears) to maintain even handling. The newer tyres should always go on the rear axle for stability, even on front-wheel-drive cars. Mixing tyre brands on the same axle is not recommended but is acceptable across different axles.
How long does it take to fit a new tyre? +
A single tyre change typically takes 15 to 30 minutes, including removing the old tyre, fitting and balancing the new one, and torquing the wheel nuts to the correct specification. If you are having all four tyres replaced, expect the job to take around 45 minutes to an hour. Mobile fitters work to the same timescales as a garage.
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.
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.
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.