CarCare

Brake pads should really be called friction pads. Brake pads use a combination of force and friction to slow the vehicle down when the brakes are applied. There are also brake shoes. The difference between the two is that brake pads clamp themselves onto a rotating disc to convert the driving force of a moving vehicle into heat in order to stop the vehicle, whereas brake shoes push out against a rotating drum in order to accomplish the same task.

Brake pads and rotors are wear items that for obvious reasons should be checked and replaced on a regular basis.
While some vehicles have disc brakes and others drums, the end result of hitting the brakes should ideally be the same either way—foot goes down and car, truck, or giant RV stops. Another function of the brake pad material is to keep the discs from getting gummed up with the friction material that the pads themselves are made of. Each time the brake pads clamp themselves onto the rotor and stop the vehicle, a small amount of the material turns from brake pad into dust. A smaller amount of the brake rotor itself also turns into dust. This dust unfortunately deposits itself all over the wheels. Brake pads and rotors are wear items that for obvious reasons should be checked and replaced on a regular basis.

Read the Signs
While swapping in a new set of pads for worn out old ones seems pretty simple, it's a task to nonetheless take very seriously. A service manual is crucial, as a mistake or shortcut made during brake assembly could have dire circumstances. Minimum thicknesses of brake pads and rotors are rules to live and keep living by. New brake pads should never be installed on worn rotors into malfunctioning calipers. Particular care should be taken with ABS systems. All that said, the next choice to be made in a brake pad replacement is the characteristics of the brake pad material itself.


In the world of brake pad material, there is no one best material that works for every situation. Brake pad material designed for everyday moderate driving will quickly overheat during performance driving and cause rapid wear along with brake fade. On the other hand, high performance brake pad material will never get hot enough to create braking friction under normal street driving. Another rule of thumb is the more aggressive the brake material, the more rapid rotor or drum wear will occur. Noise is also a concern as with greater performance more noise is to be expected.

Secret Recipe
The key to selecting the right material is to determine what type of brake pad material best suits your driving style. If driving down to the corner store and returning the occasional video is your routine, then super-performance pads are not required and may actually bring a decrease in around-town performance. If track days or canyon runs are marked out on your driving calendar, then a higher performance pad may be just the ticket as standard compounds won't hold up to that kind of driving punishment. On the everyday list of brake pads are those made of organic materials. Organic pads feature moderate stopping power and wear along with low or no noise.

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Photo Guide

After removing wheels, use brake cleaner to remove dust and grime. Do not use compressed air. Do not breathe brake dust. Always leave one side assembled for reference.

Loosen the brake reservoir cover to allow escape of air. Note brake fluid level.

Do not strip out any mounting screws if rotor removal is required. A light tap with a hammer on the screwdriver may be enough to loosen. If not, use an impact screwdriver.

On some brake systems, removal of the caliper bolts may be required to change pads. Always consult service manual for proper procedure. Always torque fasteners to specification.

Remove caliper if required. Never allow caliper to hang from brake hose. Remove old pads and note position of clips, shims, and tabs.

In this case, the locating tab on in-board rear pad must ride in groove of caliper piston for proper operation. Note that rear in-board pad has no shim installed for this reason.

To install new pads, the caliper piston must be compressed back into the caliper for clearance. Screw type pistons require a special tool.

Clean caliper piston before compressing back into caliper to help prevent contamination.

Another type of caliper piston tool is used to compress the front pistons. Note use of wire to prevent caliper from hanging.

Keep an eye on brake fluid level while compressing pistons. Brake fluid will destroy painted finishes. Siphon off excess to prevent overflow and paint damage.

Anti-vibration material can help prevent squeal, and also holds the shims in place during assembly. Apply a thin layer. Allow both sides to tack up. Mount shims to pads.

Apply a small amount of specified high-temperature grease to caliper slider pins if required.

The rear rotor was worn beyond limits and replaced. Never install new pads onto a rotor worn beyond specified operating thickness.

Install pads into caliper making sure all shims, anti-rattle clips, and tabs are in the right place. Use brake cleaner to remove any contaminants from pad surfaces before mounting caliper on disc.

Mount caliper on disc. Clean one last time with brake cleaner. Torque the mounting bolts to specifications. Follow service manual recommendations for ABS systems. Depress brake pedal to reseat caliper piston. Check disc for rotation.

The front pads were not only worn beyond limits, but also glazed. Glazing is great for donuts but no good for brake pads. Glazed brake pads suffer a loss in efficiency as they lose their bite.



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