Brake Hardware Basics

Quite often, hardware is re-used when brakes are serviced. While this is not a bad practice, there is a better way. A complete brake job should include new hardware. A common excuse was that the hardware was not in the box with the new shoes or pads. Another one was that it was just too hard to locate brake parts kits. No more excuses. As many of you probably know, Mopar® has been offering a complete line of brake parts since 2003. And if you didn’t know, now you do.

WHAT IS BRAKE HARDWARE?

Brake hardware encompasses all the parts that are used to connect and secure the main brake 
components into a complete assembly. Consider the front disc brake assembly. The main components are the caliper, the caliper adapter and the brake pads. But in order for those pieces to form an assembly, hardware is required. For disc brakes, this includes the guide pin bolts, boots and bushings (Figure 1). These bolts secure the caliper to the caliper adapter, allowing the caliper to move freely when hydraulic pressure is applied. Another hardware piece is the anti-rattle clip, which prevents rattling and noise in the brake assembly.

Drum brakes are more complex than disc brakes. There are four major components, which are the backing plate, wheel cylinder and two brake shoes. But, in order to make these parts into an operating assembly, several hardware pieces are required as can be seen in Figure 2. First of all, a holddown spring and pin are needed to secure each shoe to the backing plate. Then, an upper and lower return spring are needed to allow the in and out movement of the shoes. There is also an adjuster screw, lever and spring that is needed to automatically adjust the brakes for shoe wear. And let’s not forget the neoprene access plug that prevents water and dirt from entering the assembly.

VALUE OF NEW HARDWARE

All the brake hardware used for disc and drum brakes can be re-used. In general, the repair procedures do not state that such hardware must be replaced. There are directions for cleaning and lubricating guide pins. Also, all brake hardware should be inspected for damage. But what’s the real value in replacing the brake hardware?

As with all mechanical components, brake hardware can wear out and deteriorate from the elements and the operating environment in which it operates. Replacing brake hardware every time brake service is performed guarantees the job you have done is the best possible job that could be done. Let’s look at some of the effects that time and environment can have on brake hardware pieces.

First of all, heat and corrosion are the prime culprits when it comes to brake hardware deterioration. Heat generated from braking action, road salt, dirt and water all contribute to the weakening and wearing of brake hardware parts. Just take a look at the condition of the holddown springs and pins when you pull off the drum on a rear wheel brake assembly. If the spring wire is rusted, the spring is damaged and must be replaced. Often, though, return springs are painted certain colors and detecting damage might be difficult. Replacing the springs removes any doubt that you have re-used a potentially bad part.

Let’s look at another example with guide pins, bushings and boots. The protective boots do just that, protect the guide pins and bushings from dirt, road salt and moisture. Without the protective boots, the guide pins can rust and freeze in the bushings, which will compromise brake performance. Also, salt, dirt and water can accelerate bushing wear.

Once the hardware parts are worn and/or damaged, brake noise and premature friction material (pads and shoes) wear can occur. Aggravating squeaks and squeals will be heard and that can be really annoying to your customers. Bent or heat distorted brake hardware can cause brake linings to drag, resulting in reduced gas mileage, accelerated brake wear and a decrease in braking efficiency. Last, but certainly not least, is the potential for brake failure if a brake hardware part fails. For example, a broken brake shoe return spring can render the brake shoe assembly inoperable at that particular wheel.

Understand that adding new brake hardware is going to add to the cost of a brake job. But, you need to explain that additional cost and benefit to your customer. While other service outlets might be offering brake service at a lower cost, check to see what’s really included.

In terms of the cost for the entire brake job, brake hardware kits might be about 12 to 15 percent of the total cost. There is no increase in labor because the hardware must be removed to replace the pads and shoes. The bottom line is the benefits outweigh the cost to replace brake hardware.

Don’t forget that all Mopar brake hardware kits are specifically selected for Chrysler, Jeep, Dodge and Ram vehicles and backed by Mopar’s 12-month/12,000-mile nationwide limited warranty.

REPLACING BRAKE HARDWARE

As stated, replacing used brake hardware with new brake hardware doesn’t require additional labor. Well, there is one exception to that rule. Replacing the guide pins bushings requires removing the caliper from the vehicle as this task is best accomplished on the work bench. When this is done, the caliper and the brake lines must be bled of all traces of air. This is not something that would normally be done when installing new disc pads, but the extra time adds value to your work for your customer.

In addition to replacing old parts with new parts on drum brakes, cleaning rust and corrosion from backing plates is also important. Failure to do so can affect the performance of even new brake hardware parts.

An important note should be mentioned regarding the installation of brake springs on drum brake systems. These springs are critical to the proper operation of the drum brake assembly. If one of these springs breaks, as mentioned earlier, the brake shoes will not move in and return properly when hydraulic pressure is applied and released. When installing return springs, be very careful not to knick or gouge the spring at any spot on the spring. Always use the correct spring installation tools. Knicks and gouges can cause stress risers that can lead to premature spring failure.