At what severity must a sidewall cut on a tire be replaced?

[Linda]

Tire sidewall cuts generally require replacement when the size reaches approximately 4 millimeters. Below are precautions for tire usage: 1. Regularly correct wheel balance: Excessive wheel imbalance will cause high-frequency oscillations during high-speed driving, leading to uneven tire wear and compromising driving safety. After tire repairs, dynamic balance testing and adjustment should be performed, with the single-side dynamic balance test value not exceeding 40 grams. 2. Perform regular tire rotation: To ensure even wear across all tires on a vehicle, tires should be rotated every 5,000 kilometers, and a four-wheel alignment should be performed every 5,000 to 10,000 kilometers to prevent abnormal excessive wear. It is prohibited to install tires of different models or with significant wear differences on the same axle.