Read the final part of the tyre code
A tyre marked 205/55 R16 91V has more information than its width and rim diameter. The 91 is the load index. The V is the speed symbol. TyreSafe explains that the speed symbol states the maximum approved speed for a tyre carrying its approved load, and that it works alongside the load index.
The code sits on the tyre sidewall, but the vehicle specification remains the starting point. Check the handbook or the vehicle information label before choosing a replacement. A workshop can then confirm a suitable fitment for the axle and wheel size on the car.
- Find the full size and service description on the sidewall
- Check the vehicle's stated tyre specification before ordering
- Match tyres correctly across the same axle
Why the load index matters
The load index relates to the weight a tyre is approved to carry in the conditions it was designed for. It is part of the tyre's service description, not a styling detail. A tyre with an unsuitable load capability can undermine the vehicle specification and create avoidable handling, wear and safety concerns.
The right choice depends on the exact vehicle, wheel size and tyre specification. This matters on larger family cars, vans, SUVs and cars carrying frequent passengers or luggage, but it also applies to smaller vehicles. Ask for fitment advice when the old tyre marking, the door label and an online search do not agree.
Speed ratings do not change the road speed limit
A speed symbol describes a tyre's tested capability under its approved load. It does not grant permission to drive at that speed. Legal limits and road conditions still apply.
The practical point is tyre selection. A correct speed rating helps the vehicle handle and brake as intended. High-performance, run-flat and larger-wheel fitments often need closer checking because the original specification can be more specific than a tyre size search result.
Bring the full fitment question to the workshop
Give the workshop the vehicle registration, the tyre size shown on the car and any unusual markings you have noticed. This gives the team a better starting point than asking for a tyre by rim diameter alone.
If you are replacing a damaged tyre, start with the tyre condition. A puncture, sidewall damage or repeated pressure loss may change the immediate service route before you decide on a replacement tyre.