How Tos / Tech Articles

How to Diagnose Common Brake Issues

Brakes. No other system on your vehicle can cause so much frustration, yet be as vital to your safety. You can spend hours chasing leaks, noises, pulls, and other assorted brake maladies, only to have them crop up again.

Fortunately, the brake experts at Bendix can give you a hand diagnosing and correcting your brake woes. They put together this handy list of common brake problems, their possible causes, and suggested fixes.

Once you figure out what’s ailing your brakes, Summit Racing has the high-quality Bendix pads, rotors, drums, and other components to help you put that brake system into better-than-new condition. The smile on your face when you touch the pedal on your new binders will be thanks enough for us.

Problem: I just changed my pads and rotors. The car stops fine but every time I change direction from forward to reverse, there is a clicking noise coming from the brake.
Cause: Most modern cars have an anchor bracket style caliper that uses stainless steel clips to load the pads in a certain direction. These clips are spring steel and can wear out.
Solution: Most high-quality brake pad kits will come with new clips. If you did not get new clips, they can be purchased separately as part of a hardware kit. Be sure to lubricate the clips with a high performance synthetic brake lubricant.

Problem: I had my rotors machined and installed them along with new pads. When I apply the brakes, I hear a rhythmic thumping sound.
Cause: Rotor finish is critical to proper brake operation. A rough rotor finish acts like a screw to draw up the pads. When the pads snap back to original position, they make the thumping noise you hear.
Solution: Check freshly machined rotors for grooves. If they look like an old vinyl record, either sand the rotor surface with 180-grit sandpaper to remove any ridges, or remachine the rotors on a very slow speed to remove the ridges.

Problem: I had serious brake fade after driving down a mountain. Of course, my brakes got very hot. Now I feel the brakes fading when driving in heavy city traffic.
Cause: Brake fade is actually the brake fluid boiling. When the fluid boils, it gets air bubbles in it. These bubbles are not compressible, resulting in the fading pedal. Once this occurs, your fluid will have much less resistance to boiling over.
Solution: Always inspect your pads and change your brake fluid after any major brake fading situation.

Problem: After replacing my pads and rotors, I hear a chirping sound when I take my foot off the brakes. The sound goes away when I apply the brakes.
Cause:  Rust under the rotor can distort the rotor face. This distortion will wipe against the friction material on the pads with every rotation of the tire, causing the “chirping” sound you hear.
Solution: Clean the wheel hub surface thoroughly where the rotor mounts against it. Use a torque wrench to tighten the wheels.

Problem:  I have a lot of brake dust on my wheels. I used brake pads that are supposed to be low-dust, yet my wheels keep turning black.
Cause: Excess dust is usually due to improper caliper retraction. The caliper has a square-cut seal that is designed to keep the fluid inside the caliper. The seal also “rolls over” when the brakes are applied, kind of like winding up a rubber band. When the brakes are released, this seal unwinds and retracts the caliper piston, moving the pads away from the rotor. A worn seal will allow the pads to lie against the rotor, resulting in rapid rotor and pad wear and that ugly dust.
Solution:  If the calipers are corroded or have high mileage on them (especially on a vehicle that does not receive regular brake fluid changes), chances are the square-cut seal is fatigued. Replace the calipers with either new or high-quality remanufactured calipers.

Problem: When I redid the front brakes on my front-wheel-drive car, the brake pedal doesn’t “feel” right. I expected the brake pedal to sit higher, more like it was when the car was new.
Cause:  The rear brakes are out of adjustment. A front-wheel-drive vehicle will go through several sets of front brakes before the rears will need to be replaced, and oftentimes the rear brakes are not inspected.
Solution: Always inspect the rear brakes when you do front brake service. Remove the rear drums and check the brake shoes. If the shoes and drums are OK, clean the brake with brake cleaner and lubricate the landing area on the backing plates as well as all pivot points. Then adjust the shoes to the proper clearance. Your brake pedal will go back to its original position.

Problem: When I redo my brakes, they never seem to last as long as the original equipment brakes did. Is this because the OE pads are better than aftermarket pads?
Cause: Not restoring the brake system to OE condition.
Solution:  When you do a brake job, don’t just reline the brakes. Restore the system to like-new. Use new or properly machined rotors. Use premium friction materials. Disassemble the caliper as far as possible and clean it thoroughly to remove all rust and corrosion. Replace the caliper hardware and lubricate everything per spec. Bleed and flush the brake fluid. Burnish the pads for proper break in. The result will be new brakes that will last as long as the original brakes did.

Problem: I have a late model vehicle with antilock brakes. Just before I come to a complete stop, my pedal drops and pulsates. It only does this below 8 miles per hour and not all the time.
Cause: Dirty or rusty ABS sensors.
Solution:  Whenever you are doing brake work, inspect and clean the ABS sensors. Carefully clean the sensors with brake cleaner and remove any metal filings. Inspect the tone rings for cracks or missing teeth and replace as necessary.

Problem:  I am having a hard time getting my pads to fit in the caliper anchor. I put the new clips in and the pads fit so tight I am afraid they will not work properly.
Cause: Rust on the anchor brackets.
Solution: Clean the brackets thoroughly and inspect them for wear. If the anchor is worn, it needs to be replaced. If there is rust under the clip, it can cause brake drag and/or uneven wear.

Problem: My brakes are dragging after doing a routine brake job.
Cause:  When pressing the caliper pistons in, you can force too much brake fluid back into the master cylinder. This can block the vent on the master cylinder, causing the brakes to slightly self-apply when they are warm. You can also push the caliper piston into the dirty fluid accumulated in the caliper piston bore, causing the piston to stick.
Solution: Flush out the dirty fluid by attaching a hose to the caliper bleeder screw, opening the screw, and bleeding the fluid into a suitable container. This prevents the master cylinder from becoming over-full and stops dirty fluid from being pushed backwards into the braking system.

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  1. Pingback: Garage Goal #7: Maintaining or Repairing Your Brakes - OnAllCylinders

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