A new tyre has about 7-8mm of tread and although the legal minimum is 1.6mm across the central three quarters of the tyre, recent research recommends you change your tyres at 3mm for your safety and performance*.
It is imperative that you leave enough space between you and the vehicle in front so that you can pull up safely if it suddenly slows down or stops. The table below shows how various speeds affect your total stopping distance:
Note: these distances are general guides – they will depend on your attention (thinking distance), road surface, weather conditions and condition of your tyres and vehicle at the time. Average car length – 4 metres.**
*RoSPA
**Direct.gov