2000 Chevrolet Blazer - Wheel Cylinder

Why is my Wheel Cylinder Leaking?

A drum brake system's wheel cylinder is a vital hydraulic component that helps stop your car by using brake fluid to pressurize and extend its two pistons. When you apply your brakes, the wheel cylinder receives hydraulic pressure that forces the brake shoes against the brake drum, generating friction that slows down your vehicle. The brake shoes are held in place against the backing plate and use springs that pull the shoe away from the drum when brake pressure is released. Your wheel cylinders are crucial to safely and successfully handling your car on the road, helping you prevent an accident and providing smooth, controlled stopping performance. Since you can't see most of the wheel cylinder from the outside of the vehicle, it's important to know the signs of wheel cylinder and brake system failure for a safer drive. Over time, wheel cylinders can develop brake fluid leaks or corrode - this may cause low brake pressure or a stuck piston which can keep the brake shoe engaged and lead to premature wear. Excessive heat caused by friction, exposure to moisture, and general wear can also cause your wheel cylinders to degrade, leak, or ultimately fail. Signs of a bad wheel cylinder include poor brake response, a soft or spongy brake pedal, as well as brake fluid leaks, contamination, or a slight film of brake fluid on the backing plate. If you notice these symptoms, be sure to check your wheel cylinder for damage. Continuing to drive with a bad wheel cylinder can affect your vehicle's ability to slow or stop, and if the wheel cylinder fails entirely, you may lose all brake pressure. This can prevent you from stopping entirely, so it's best to replace a bad wheel cylinder as soon as possible. When replacing a wheel cylinder, be sure to also inspect your brake drums and shoes for signs of wear or damage, and either resurface or perform a DIY drum brake repair if necessary. O'Reilly Auto Parts offers brake drum and rotor resurfacing at many of our locations to help you save time and money on your repair. After replacing a wheel cylinder, it is also important to know how to bleed brakes since your brake lines will likely have air trapped in them and the brakes will be spongy. O'Reilly Auto Parts carries complete wheel cylinders, brake tools, brake fluid, brake cleaner, and more for a complete drum brake repair to keep you safe on the road. Make your repairs less of a hassle with resources from our How-To Hub with topics like symptoms of brake failure, and much more.