Is it allowed to fit tyres with a different speed rating than the one recommended by the manufacturer?
- A)Yes, always.
- B)No, it is forbidden.
- C)Yes, as long as the rating is higher than the recommended one.✓ Correct answer
Why this is the correct answer
The speed rating (a letter on the tyre sidewall, e.g. H, V, W) indicates the maximum speed the tyre can safely sustain. Spanish regulations (Royal Decree 866/2010 and ITV inspection criteria) require that the speed rating of your tyres must be equal to or higher than the one indicated in your vehicle's technical data sheet (ficha técnica). A higher speed rating means the tyre is built to handle greater forces at higher speeds, so it offers an additional safety margin — this is always permitted. However, fitting tyres with a LOWER speed rating is prohibited because the tyre may not withstand the forces generated at the vehicle's maximum speed, leading to overheating, loss of grip, or even a blowout. If you do this, your vehicle will fail the ITV (roadworthiness test) and you may be fined. Note: The only exception is for winter tyres (marked M+S or 3PMSF), which may have a lower speed rating, but never below Q (160 km/h).
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