Brake calipers are a vital part of your vehicle's braking system. The calipers squeeze the brake pads against the surface of the brake rotor to slow or stop the vehicle. When you step on the brake, brake fluid from the master cylinder creates hydraulic pressure on one or more pistons in the brake caliper, forcing the pads against the rotor.Brake calipers don't need to be replaced very often. But, when they do need replacing here are some of the warning signs you may notice. If a caliper is sticking, the vehicle could pull to one side when the brakes are applied. If a caliper is completely seized, serious damage to the brake rotor and other braking components is likely, increasing the potential cost of brake service dramatically.From a safety standpoint, faulty brake calipers may dramatically increase the distance required for you to stop, cause the vehicle to pull to one side, or result in loss of control which could result in injury to you and possibly others. Neglecting brake caliper maintenance has no environmental impact.