Brake vibration

lexus
brakes
vibration
ls

#1

I just replaced the front rotors and brake pads to stop a bad vibration during braking. The problem is still there, although not as bad. What could be the cause?


#2

Idea 1: Do these brakes have springs? Are they all there?
Idea 2: Any signs of wear on the caliper guides? If they are not gliding back and forth properly you could be getting some rubbing. Did the old ones come off with even wear?
Idea 3: Bad wheel bearing or bearing hub depending on make/model.


#3

It’s possible some of the problem was in the rear brakes as well. Does the vibration feel like it’s in the seat or in the steering wheel? If it’s the seat, the problem is in the rear. Also, you could have some corrosion on the hub behind the hat of the rotor. This will cause a runout problem and could cause a vibration. Check for corrosion and, if present, clean it off. You may have to use a chisel if there are high spots of corrosion on those hubs.


#4

I would check the hubs first as mark9207 said. One other important thing to pay attention to along those lines is the lug nut torque on the wheels. Over torque and/or uneven torque will make a mess of rotors. Find out what the specs are and it is best to use a torque wrench.

You can check to see if the rear brakes are producing any vibration by using the parking brake. Somewhere on a nice, open, empty stretch of road, apply the parking brake. If you get vibration then you still have a problem in the rear.

But you really should also go get the front end inspected. A bad wheel bearing (as neumann5 noted) or other front end problems (e.g. bad tie rod end) can also produce vibration when braking - especially if the hubs have some gunk on them.


#5

You can check to see if the rear brakes are producing any vibration by using
the parking brake. Somewhere on a nice, open, empty stretch of road, apply
the parking brake. If you get vibration then you still have a problem in the rear.

This is a good diagnostic step in all cases except where the rear brakes are discs with the internal drum-parking brake. More rear disks are setup this way.