Reading the size on your tyre
Your tyre size is moulded into the sidewall, usually in raised letters about a third of the way down from the tread. It looks like this:
Width, profile and rim
The first number is the tyre's width in millimetres. The second is the profile: how tall the sidewall is, as a percentage of the width. The R means radial construction, and the number after it is the wheel diameter in inches.
These three numbers must match your car exactly. If your front and rear tyres are different sizes, search for each one separately.
Extra load and run-flat
XL or "reinforced" tyres carry more weight at the same size. If your car came with XL tyres, replace them with XL tyres.
Run-flat tyres let you keep driving for a short distance after a puncture. They may be marked RFT, ROF, SSR, ZP or with a circled "RF". Cars built for run-flats often have no spare wheel, so keep using them.
Speed ratings
The letter after the load index is the highest speed the tyre is designed for when fully loaded. Your new tyres should have the same rating or a higher one.
| Rating | Up to (mph) | Up to (km/h) |
|---|---|---|
| N | 87 | 140 |
| P | 93 | 150 |
| Q | 99 | 160 |
| R | 106 | 170 |
| S | 112 | 180 |
| T | 118 | 190 |
| H | 130 | 210 |
| V | 149 | 240 |
| W | 168 | 270 |
| Y | 186 | 300 |
Load index
The load index is the most weight each tyre can carry at full pressure. Use the same number or a higher one.
| Index | kg per tyre | Index | kg per tyre | Index | kg per tyre |
|---|---|---|---|---|---|
| 70 | 335 | 88 | 560 | 106 | 950 |
| 71 | 345 | 89 | 580 | 107 | 975 |
| 72 | 355 | 90 | 600 | 108 | 1000 |
| 73 | 365 | 91 | 615 | 109 | 1030 |
| 74 | 375 | 92 | 630 | 110 | 1060 |
| 75 | 387 | 93 | 650 | 111 | 1090 |
| 76 | 400 | 94 | 670 | 112 | 1120 |
| 77 | 412 | 95 | 690 | 113 | 1150 |
| 78 | 425 | 96 | 710 | 114 | 1180 |
| 79 | 437 | 97 | 730 | 115 | 1215 |
| 80 | 450 | 98 | 750 | 116 | 1250 |
| 81 | 462 | 99 | 775 | 117 | 1285 |
| 82 | 475 | 100 | 800 | 118 | 1320 |
| 83 | 487 | 101 | 825 | 119 | 1360 |
| 84 | 500 | 102 | 850 | 120 | 1400 |
| 85 | 515 | 103 | 875 | 121 | 1450 |
| 86 | 530 | 104 | 900 | 122 | 1500 |
| 87 | 545 | 105 | 925 | 123 | 1550 |