Replace struts when the vehicle experiences excessive bouncing, the nose of the vehicle dives, the rear end squats, the tires show signs of cupping or the hydraulic fluid leaks excessively. The struts are a primary component of the suspension system, and damaged or worn struts create a serious safety hazard.
When the vehicle travels over a bump and bounces excessively, the shocks or struts require replacement. During acceleration, if the rear end of the vehicle dips, then the struts need replacing. Another sign of the struts requiring replacement is when the vehicle leans drastically to one side while turning left or right. The struts also need to be replaced when the tires make contact with the ground and small bits of rubber are scraped off. This is known as cupping.