Tyres are the only connection between your car and the road. The condition of your tyres is critical to maintaining good handling and safe stopping distances. Tyres have a legal minimum tread depth, and they must be replaced when they reach that point. Driving with damage to the tyre sidewalls is dangerous and can result in a blow-out.
Haynes Ford recommends that tyres are replaced when they reach a tread depth of 3mm or if there is any damage to the sidewalls, to ensure the road holding and safety of your car is not compromised.