The mechanical motion of the Mercedes-Benz disc brake caliper is powered by the hydraulic pressure the brake system can generate. This is the action component of the braking system that provides the means for the friction to be generated when pressure is being applied to the brake pedal so your Mercedes-Benz vehicle will slow down. There is a Mercedes-Benz disc brake caliper on each wheel that utilizes the disc braking system. Some models only have this system on the front, while others have 4 wheel disc brakes on them. Each one is powered by the pressure created in the hydraulic system from the brake master cylinder. The only component of the disc brake caliper that is moves is the piston. The hydraulic pressure from the master cylinder pushes this piston out when the brake pedal is being forced down. To keep the hydraulic fluid in place there is a polymer seal around the piston and cylinder wall. This is the braking component that will fail on the disc brake caliper. This seal fails because it is made out of flexible polymer that will crack over time cause the hydraulic fluid to leak on your Mercedes-Benz. The replacing of the disc brake caliper is not a complicated process. The most difficult part of this rprocess is the removal of the brake hose. This braking component might be stuck since it is not generally removed unless the disc brake caliper is being replaced or the hose itself is being replaced because it is leaking. The brake hose removal while the caliper is still mounted will help to prevent it from becoming damaged during the repair process. It will also make its removal easier on your Mercedes-Benz.