If you are unsure if your vehicle is getting ready for some new tyres, follow these points and see if your tyres are legal and safe. Look for a marking on the side wall of the tyre which says TWI - Tread Wear Indicator - Follow this across the tyres and you will see raised indicators, if these are level, not below, the level of the tread it is a sign they are ready for replacement. http://www.challengertyres.com http://www.twitter.com/challengertyres http://www.facebook.com/challengertyres