Without a rear wheel cylinder, your car would not be capable of functioning and safely stopping when the brakes are applied. It is a very small but crucial part of the braking system in your vehicle. This is one of the major reasons you must maintain your brakes regularly.

Where is the Rear Wheel Cylinder?

It is positioned above the brake shoes at the top section of the wheel. The main function of the cylinder is to apply force to the shoes and make contact with the drum. This causes friction to make the vehicle stop when you step on the brake pedal. Small rods connect the shoes with the wheel cylinder. If the cylinder begins to leak, the car's brakes cannot perform, and the car might not stop.

How Does it Work?

A set of pistons is on each side of the cylinder connected by a plunger and rubber seals. With pressure, the pistons force the shoes to come in contact with the drum. Pressure sends the brake fluid to the rear and front brakes. The plunger mechanism dictates the amount of fluid sent in response to the amount of force used on the brake pedal.

For example, if you lightly tap the brakes, only a small amount of fluid is released. If you place more pressure such as a quick stop, more fluid is released to the brake shoes. Less power is required for smaller vehicles, making a lighter braking system. For larger vehicles, a more heavy-duty system is required. The designs may vary depending on the make and model of the vehicle.

The older cylinders were made of cast iron which had a tendency to rust. With advanced technology, many of the manufacturers now use aluminum. As previously mentioned, caution must be used for leaks in the wheel cylinder when the unit is worn out.

What Problems Are Possible?

The plunger and rubber linking may erode and make it ineffective to pass the brake fluid to the brake line of the wheel cylinder unit. This is what causes the fluid to leak. Therefore, air will enter the vehicle's brake system and reduce the power needed to stop the car. The result is a mushy brake pedal, and will require the lines to be repaired. The lines also will need to be bled to get fluid back into the brake lines.

This is the way rear wheel cylinders operate. If you have the skills to understand the process, you should not have much difficulty repairing the brake system. However, if you are not knowledgeable of the process, it is a good idea to have a professional do the work. After all, safety is the number one factor for your automobile.

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