Understanding Tyre Markings and What They Mean
That string of numbers and letters on your tyre sidewall contains crucial information. Here's how to decode it and why it matters when ordering replacements.
Every tyre carries a standardised code on its sidewall that tells you everything from its size and load rating to its speed capability. Understanding this code ensures you always order the correct tyres for your vehicle — a critical safety consideration.
Take the marking 205/55 R16 91V as an example. The first number (205) is the tyre width in millimetres. The second figure (55) is the aspect ratio — the height of the tyre's sidewall as a percentage of its width. 'R' denotes radial construction (the industry standard today), and 16 is the rim diameter in inches.
The '91' is the load index — a numerical code indicating the maximum weight each tyre can support. 91 equates to 615 kg. The final letter 'V' is the speed rating, indicating the tyre is approved for continuous use at up to 240 km/h (149 mph). Using a tyre with a lower speed rating than recommended can void your insurance.
You may also see markings like XL (extra load), RF (run-flat), or MO (Mercedes original equipment). Always ensure any replacement tyres match your vehicle manufacturer's specification at a minimum. When in doubt, share your registration plate with a reputable supplier like Trident Mobile Tyres — we'll identify the correct fitment for your vehicle.
Related Topics
