its probably the trim in your car hanging loose or if its your whole chassis you might want to take the car tested and replace the brake pads
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The brake rotors are warped. Have them turned or replaced. This is a very common problem, i see it all the time. You may as well replace the pads while you are at it.
brake rotors out of round
You have a "Warped" brake rotor. It needs to be replaced
the cuase of this is ussaully worped rotars
you most likely have warped brake rotors
Brake rotors are warped.
Normally this is caused by warped brake rotors.
Could be a frozen brake caliper or a rotor that is "out of round".
because the alignment is off Warped or out of round brake rotors/drums.
That usually happens when the front brake rotors are out of round. It is a common problem, and they can either be replaced or re-ground so that they are true again.
A car shaking while applying brakes is most likely caused by worn a brake pad. Check the brake system at all four wheels to find the problem.
If a car shakes during acceleration the brake rotors may be damaged. If the rotors are damaged they will be unstable as the tires rotates making the whole car shake.
Warped rotor and worn out brake pads.