The first question we ask on every call is "what size is the tyre?". It is not us being awkward. Our mobile vans carry stock, and knowing the exact size before a fitter sets off means they arrive with the right tyre on board instead of making a second trip. At night and at weekends it makes the difference between one visit and two.
Where to find the size
Look at the sidewall of the tyre, the flat side facing out from the car. You will see a row of numbers and letters moulded into the rubber, usually something like:
225/40 R18 92Y
On a dark night a phone torch held at an angle makes the lettering much easier to read. If the tyre that has gone flat is on the side next to traffic, read the size from the tyre on the other side of the same axle instead, as it should be the same, and stay safely off the road while you do it.
The size is also often printed on a sticker inside the driver's door frame, inside the fuel filler flap or in the vehicle handbook, but the tyre itself is the most reliable source because a previous owner may have changed the wheel size.
What the numbers mean
| Marking | Meaning |
|---|---|
| 225 | Width of the tyre in millimetres |
| 40 | Profile: the sidewall height as a percentage of the width |
| R | Radial construction |
| 18 | Wheel rim diameter in inches |
| 92 | Load index: the maximum load each tyre can carry |
| Y | Speed rating: the maximum speed the tyre is built for |
When you call, the first three numbers (225/40/R18 in this example) are what we need. If you can read the load index and speed rating too, even better, because we will match them.
Vans, trucks and plant
Commercial tyres follow the same idea with a few extras:
- Vans usually show a C after the rim size, for example 215/65 R16C, and two load numbers such as 109/107. The C means commercial and the tyre is built for heavier loads.
- Trucks and trailers are often sizes like 315/80 R22.5 or 385/65 R22.5. Tell us which axle the tyre is on: steer, drive or trailer.
- Plant and agricultural tyres may use older markings such as 405/70-20, 12.5/80-18 or 18.4-26. Read out everything on the sidewall and we will work it out.
Have your full location ready too
The other thing we need is exactly where you are. A postcode helps, but on a long road or an industrial estate we also need a landmark, a unit number or a what3words reference. On a motorway, give us the carriageway, the nearest junction and the number on the marker post. Our motorway assistance page explains how to find it.
With the size and location ready, call our 24 hour line on 07912 478216. Still not sure about your size? Our tyre size guide has photos of where to look.
Our mobile units work 24 hours a day, 7 days a week. Call 07912 478216 or 0161 205 1362, or get a quote online. Have your tyre size and full location ready.