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Dear James, My 1996 Chevy 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. 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? T.O. Callaway

Dear T.O. A lot of shops will do a “brake job” by replacing pads and brake shoes to stop brake noises. This fix does not stop the noise permanently! All the parts on a brake system under the car should be replaced/ 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 they have not kept up with the changing “composite” type braking systems of today’s vehicles. 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 brakes. The caliper piston that moves out to “squeeze” the pads against the rotor has a rubber square cut “O” ring to hold the brake fluid in, and dirt out. This “O” ring gets hard after about 45,000 miles. When these parts get hard and have lost their flexibility, the noise will start! That is another reason why your disc brake pads wear out too fast. They never “retract” from the disc brake rotors! They are always rubbing against the disc brake rotor! When this happens it cuts down on your gas mileage as well as your brake pad life. The disc brake pads get too hot! When this happens, resins in the brake pads come to the top of the pad. This lets the pads vibrate causing the brakes to make noise and not stop as well. Some people compare it to “fingernails across a blackboard” I think that just about sums up the description of the noise you are hearing, and what actions are needed to correct this problem. James Morris

 

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