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A disc brake rotor with excessive run out is a warped rotor which causes a pulsation in the brake pedal when the brakes are applied. A certain amount of run out is acceptable.
disc brake components
The rotor is the disc in the disc brake system.
Disc brake rotor? A pulsation in the brake pedal when applied. Distributor ignition rotor? The engine may not run or run poorly with misfires.
In case of cost..drum brake is better than disc brake.
There are many purposes to using a disc brake. Disc brakes are mainly used in industrial drills because the disc brake stops the drill gently so it doesn't overheat.
Disc brake pads and drum brake shoes
pad brakes are disc brakes, it's known as changing brake pads for disc setup and changing brake shoes with drum brake setup.
The teves caliper is a single piston disc brake caliper and the akebono caliper is a dual piston disc brake caliper. The teves caliper is a single piston disc brake caliper and the akebono caliper is a dual piston disc brake caliper.
It looks like a hydraulic clamp. When hydraulic pressure is applied with the brake pedal, the caliper clamps the disc brake pads to the disc brake rotor to stop rotation.
With rear drum brake:-The brake drum may be out of round or may have a rust spot in it. -The brake drum may be cracked.With rear disc brake:-The brake disc may have extreme lateral runout or be mounted improperly. -The brake disc may be cracked. This would be dangerous-Combination of soft brake pads and a directional finish on the disc surface. A directional finish may go away with use and take the noise with it.Regardless of brake type:A brake disc or drum mounted to a bent hub flange or bent axle shaft can cause this noise.