
Methods to check the tread depth of car tires: 1. Prepare a tire tread depth gauge; 2. There are six triangular symbols around the sidewall of the tire. Following the direction indicated by the arrows, you can feel multiple raised steps in the tire grooves; 3. Insert the tip of the gauge into several main treads in the same cross-section of the tire tread to measure the depth. More relevant information is as follows: Braking, acceleration, and steering between the tire and the ground are all achieved through the tread patterns on the tire. The tread pattern has a significant impact on the tire's performance. The deeper the tread, the greater the elasticity generated between the tread and the ground, resulting in stronger grip.

I usually check tire tread depth by inserting a one-yuan coin vertically into the tire grooves. If the lotus pattern on the edge of the coin is completely visible, it means the tread depth is already less than 3mm. New tires typically have a tread depth of about 8mm, and they should be replaced before reaching the legal minimum limit of 1.6mm. A handy tip is to look for the triangular wear indicator mark on the tire sidewall – the corresponding groove has a raised rubber block, and when the tread wears down flush with this block, the tire is absolutely unsafe to use. I check all four tires for wear during my monthly car wash, especially the front tires on front-wheel-drive vehicles which tend to wear faster. If you notice longer braking distances or skidding in rainy conditions, it's likely due to worn treads impairing water drainage.

Measuring tire tread depth doesn't require professional tools - a bank card will do. Insert the card into the deepest groove of the tread, mark the edge, then measure this distance to get the actual depth. Consider replacing tires when it's below 4mm, especially for frequent highway drivers. Winter tires have higher requirements - I've heard snow traction significantly decreases below 5mm. During routine checks, also watch for uneven wear. If the inner side wears particularly fast, it might indicate wheel alignment issues. I always bend down to inspect tires before long trips - safety comes first.

The simplest way to check tire tread is to look for the wear indicators. All qualified tires have raised rubber blocks in the grooves with a height of 1.6 mm. When the tread wears down to this level, the tires must be replaced immediately. I usually test it with a key: insert the key vertically into the tread groove, and if the teeth touch the raised block, that's the warning point. Remember to measure at three positions: the center and both inner and outer sides of the tread to avoid uneven wear affecting safety. If you notice the tread pattern becoming indistinct during summer driving, the braking distance can increase by two to three meters, which is particularly dangerous.


