Because the brake shop used an air impact wrench to install the wheels. Incorrect or mismatched torque on the wheel lug nuts will warp the stock flimsy rotors. Either, have the shop manually torque the wheels and/or install higher quality rotors. Once the damage is done you can't undo it without machining the rotors or replacing them. Machining flimsy rotors just makes them easier to warp next time Are you sure that your pulsation is coming the front brake rotors.Test drive your vehicle in large parking lot where there are no cars or very few cars.Do not exceed 10 mph.Gently engage the parking brake without applying the brake pedal.If you feel a pulsation,your problem is in the rear.Machine or replace the brake drums/rotors and shoes/pads.If the pulsation can be felt in the steering wheel,remove wheels,remove calipers and brake rotors.Check for rust on the wheel hub(this is the area directly behind rotor where wheel studs are located).If rust exist remove with wire brush.Next check guide pins.These should move with minimal effort using your hand.If there is no problem with rust or frozen guide pins,measure rotors,machine or replace if not within specs. and replace pads.If you are using a air operated impact wrench use a toque stick with least amount toqure.The next step is very important USE A TORQUE WRENCH.You can borreow one from most major part store chain such AutoZone and O'Reilly.Please me know if this solves your problem.
The front rotors are out of round or warped, Need to have the rotors turned.
Do you have anti lock brakes that might be it if not your rotors maybe warped
Rotors out of round and need to be replaced or resurfaced?
Warped rotors. Driving using the left foot to brake causes the rotors to heat up. Quenching the hot rotors by driving thru water will cause them to warp. The warped rotors cause the pedal to pulsate.
If you're changing the brake pads and there is too little rotor thikness to turn it, it should be replaced. If the rotor is warped and is too thin to be able to turn to remove the warping, replace it. If the brakes "pulsate" when you use moderate brake pressure, the rotor is warped.
The rotors are out of round, WARPED. Need to have them turned and replace pads too.
For the brakes, check for warped rotors. For the turning, check for worn CV joints.
200
You have warped the brake rotors. Driving fast & hard stopping or riding the brake will cause this when the rotor is hot and you are stopped with heavy pressure on the brake pedal. Replace rotors and pads.
how to replace break pads on 2001 4runner
If it is a Toyota, they do not know how to fix the squeaking brakes either. Even after replacing all the pads and machining the rotors and rear drums
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