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Dear James, My 2004 Chevy 1/2 ton truck has a brake noise in the morning when I first apply them. It is a low sounding type growl like a metal to metal sound. As the day goes on they occasionally squeal a high pitch irrating sound. I have had the brake pads changed twice in the last 3 years hoping to stop this problem. It goes away for about 4 to 6 months then it comes back. Any ideas on how to stop this brake noise? Tom O. Callaway

Dear Tom, A lot of shops will do a “brake job” by replacing pads and brake shoes to stop brake noises. The problem is, it just doesn’t stop the noise permanently. All the parts on a brake system that gets “hot” need to be replaced or rebuilt when doing a complete brake job. Let me explain what I mean when I say a complete brake job. Changing pads and shoes and turning the drums and rotors are what 90% of most shops do when they do a “Brake Job”. In truth they are just doing a “Brake Re-Line” not a brake overhaul. The reason they do this type repair is due to lack of knowledge of what is causing the brake noise with today’s vehicles braking system Today’s brake calipers have rubber “insulators” that get old and hard and won’t absorb the vibrations that are produced when you apply your trucks brakes. Inside the brake caliper is a piston that moves out to “squeeze” the pads against the rotor when you press on the brake pedal. It is a rubber square cut “O” ring to hold the brake fluid in, and dirt out under really high hydraulic pressure. This “O” ring gets hard after getting so hot stopping your vehicle over the years of driving. Now this “O” ring has developed a “directional shape”. If you push this brake caliper piston back into the caliper to install new pads, it disturbs this square cut “O” ring. When you take your foot off your brake pedal, the brake caliper piston is not able to retract from the new brake pads. This slight amount of pressure to your disc brake pads causes excessive brake dust and heat. The heat that is produced allows the resins that are baked inside of the new brake pads come to the surface of the brake pad. These resins become very hard when the vehicle cools off. They act like tiny phonograph needles on the brake rotor. Following the tiny grooves in the brake rotor allowing the brake pads to vibrate and make noise. Some people compare this irritating noise to “fingernails across a blackboard” when they stop their vehicle. If you want to save money and get better fuel mileage and stop the noise. Find a shop that will repair your brakes “right the first time”. If you want to watch the video on what needs to be done. Just Google “No return brake job” it will be informative as well as eye opening on what procedures are needed to fix your car “right the first time”. Peace and prosperity in 2012! James Morris

 

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