You may already know that the legal limit for tread depth on regular road tires is 1.6 mm. However, keep in mind that safe driving in wet and snowy weather conditions is affected by the tread depth, pattern design and rubber compound of the tread of your tires. On wet or snow-covered roads, braking performance will progressively decline with lower tread depths. On wet roads, there is an additional increased risk of aquaplaning with fading tread depths.
The legal limit for tread depth also applies to small to medium SUVs or crossovers.
Therefore, check your tires regularly.
If you own an SUV with 4X4 capabilities, the limitations for tread depth are different. Some off-road tires may begin with 20 mm of tread depth, but once they get worn down, the tire will stop working effectively and will be unsafe. As you can imagine, once the shoulders and tread of an off-road tire get worn down, it will have far less traction on tough terrains like mud, grass, and snow.
Whether your SUV has 4X4 capabilities or not, you will know when it’s time to replace your tires by its tread wear indicators (TWI). Sometimes known as wear bars, they are evenly spaced throughout the grooves of the tire tread. If they are level with the tread, the tire must be replaced as soon as possible