The protective cover of the car cage is generally more durable. Once damaged, the service life of the repaired cage protective cover is generally 2-3 years. The following is an introduction: 1. Main function: The car holder is divided into an inner holder and an outer holder, also known as a "constant velocity universal joint". The main function of the cage sleeve is to prevent dust from entering the cage and prevent lubricant loss. After damage, it can cause dry grinding, and in severe cases, it can lead to the scrapping of the half shaft, which requires routine inspection. 2. Service life: The service life of the automobile ball cage universal joint basically depends on the service life of the protective sleeve, and the service life of the ball cage sleeve also depends on the process and materials.