Bad Shaking Vibration when I hit the brake pedal?

[Brutal Metal]

This has been going on for a couple months now, I'm not getting an ABS light on the dash. It's weird cause If I hold my foot on the pedal for a few seconds it'll go away. It's initially pretty bad you can feel it in the steering wheel. Could something be binding up/sticking? Any brake system Pros in here?

 

[PhoenixM3]

Do you use your brakes gently? If so, maybe you have some brake pad residue (not sure if that’s the prop term) build-up. I think you could eliminate this by doing repeated stops using very heavy braking at highway speeds.

It might be something as simple as a lost wheel weight too. Cheaper to have the front wheels re-balanced then to replace rotors and pads. Good luck.

 

[Zemedici]

How do the pads / rotors look?

 

[MG0h3]

Likely warped rotors.


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[Brutal Metal]

Do you use your brakes gently? If so, maybe you have some brake pad residue (not sure if that’s the prop term) build-up. I think you could eliminate this by doing repeated stops using very heavy braking at highway speeds.

It might be something as simple as a lost wheel weight too. Cheaper to have the front wheels re-balanced then to replace rotors and pads. Good luck.

I changed my rotors and pads a year ago less than 7K miles.

 

[Brutal Metal]

Likely warped rotors.


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I got fresh centrics they look nice and smooth in the contact area all 4 tires.

 

[Brutal Metal]

I've been told it could be something with the ABS?

 

[PhoenixM3]

I've been told it could be something with the ABS?

Not likely. An ABS problem might not be noticeable unless you tried to brake hard and had one wheel lock prematurely. Unless you drive (and brake) hard and then park your car with scorching hot brakes, you shouldn’t have been able to warp rotors. Get the front wheels balanced. Tell us wha you find.

 

[Brutal Metal]

Not likely. An ABS problem might not be noticeable unless you tried to brake hard and had one wheel lock prematurely. Unless you drive (and brake) hard and then park your car with scorching hot brakes, you shouldn’t have been able to warp rotors. Get the front wheels balanced. Tell us wha you find.

Yeah it's for sure the front where the issue is..

 

[MG0h3]

Jack the front of the car up. Spin the wheel. You may hear the pads scuff the rotors in a rhythmic or on/off type of patter as the wheel spins.

Is is most noticeable coming down from freeway speeds?

 

[Mojo88]

Almost guaranteed to be rotor-related. And if you feel it in steering wheel, that usually means front brakes. If you feel vibration more in the seat, then that would indicate rear brakes.

First thing to do is (as already stated) take front wheels off and inspect brakes and calipers. If you have a dial caliper, you can check for rotor runout real easy, I'm assuming you know how to do that. But even if the runout is minimal, you could have a rotor that has a spot of buildup on its surface, perhaps from overheating or whatever, even if the rotor has low miles on it.

In the old days (when I had my service station in the 70's and 80's), I would have recommended to get the rotors turned. We turned rotors and drums every day on my brake lathe machine. But nowadays, new rotors are inexpensive and usually of good quality, so I always recommend brand new. Anyway, my guess is that two new front rotors will likely fix you up real nice, assuming pads and calipers are OK.

 

[Brutal Metal]

Jack the front of the car up. Spin the wheel. You may hear the pads scuff the rotors in a rhythmic or on/off type of patter as the wheel spins.

Is is most noticeable coming down from freeway speeds?

Yes it's worse 50 mph and higher ...

 

[Brutal Metal]

I would have recommended to get the rotors turned. We turned rotors and drums every day on my brake lathe machine. But nowadays, new rotors are inexpensive and usually of good quality, so I always recommend brand new. Anyway, my guess is that two new front rotors will likely fix you up real nice, assuming pads and calipers are OK.

I did install brand new when I bought the car a year ago. Also if I have bad runout why does the vibration go away after a couple seconds with the pedal depressed?

 

[Mojo88]

I did install brand new when I bought the car a year ago. Also if I have bad runout why does the vibration go away after a couple seconds with the pedal depressed?

From my desk here, all I can do is make some educated guesses. So my 'guess' is that a contaminant of some sort got on the rotor surface, perhaps the rotor was improperly cleaned before installation, or maybe someone got a nice greasy fingerprint on it during installation. Then, over time, that spot changes the surface of the rotor so that it is no longer even.

Another 'guess' is; maybe the caliper is hanging up - the guide pins often get dry and then the caliper doesn't fully release, then heat builds up, and well, the whole assembly (calipers, pads, rotors) needs to be replaced at that point.

You should also check out the wheels, tires and front end components before replacing any parts.

Bottom line: it's a relatively easy fix, once you get correct diagnosis.