Installed new rotors and pads - vibration problem

[Nic01101011]

I installed new rotors and pads all around today, and under moderate to hard braking I feel a vibration, almost feels like ABS, and hear a thumping noise from the front right.

at first I thought it was the tire hitting the plastic fender liner, but that isn't it.

the rotors are Brembo blanks, quality I thought. what are the odds of getting a warped rotor from them?

any ideas?

[asubimmer]

are you using the bolts that hold the rotors in place? Take the wheels off and make sure the rotors are seated right and everything it tight.

[Nic01101011]

are you using the bolts that hold the rotors in place? Take the wheels off and make sure the rotors are seated right and everything it tight.

yea checked that lot several times, everythings tight and in place

[jlevie]

While possible, I'd say that the odds are that you don't have a warped Brembo rotor. I'd be more suspicious that the rotor isn't fully seated on the hub, you haven't bedded in the pads, you've managed to to get uneven pad deposits on the rotors, there are worn suspension parts, or that you have a tire/wheel problem.

[Nic01101011]

The thing is there was no vibration before the change. So I suspect it's part of the braking system.
I did bed in the pads according to the instructions, got them nice and smelly.

I tightened the little screw that holds the rotor to the hub, and brushed off what little rust there was where the rotor seats. But of all things mentioned the rotor not being fully seated sounds most plausible.. ill have another look tommorow

[daniel]

did you torque your wheels properly? sometimes if you overtighten them you can "warp" the rotors.

[FreedS4]

I'm having the same issue. Just replaced the pads and rotors today. Any idea what the cause was for you? Thanks in advance.

Chris

[FreedS4]

So I've still got this issue. I went ahead and put in new control arms and M3 CABs, still nothing. I swapped the pads from the passenger's side to the driver's side to see if that was the issue and nothing changed. Any ideas?

Chris

[zedfez]

Did you check the hub surface behind the rotors? If you get crud in there the rotors will never seat right. Also make sure your caliper bolts are tight. It seems stupid but I know of more that one occasion where that was the culprit.

[FreedS4]

I've checked and double checked both, to no avail. I'm really puzzled as to what it might be, because I've never had this issue before.

[FreedS4]

So here's another interesting part of this saga, I swapped the driver's side and passenger's side rotors and the noise followed the rotor. That is to say, now the sound is coming from the driver's side. Would a warped rotor have these symptoms and make this noise?

Chris

[3bvert]

yes
if you have a harbor freight near you you can get a dial indicator adn stand for under 30 bucks, and you can check if the rotors are warped on the car
you can also do it with a sharpie, a vice grip a c clamp adn a chair. set the sharpie in the vice grip and clamp to the chair. move the chair so it is a papers thickness away from the rotor, spin the rotor, see if you get any marks on the rotor, if you do, its probablly warped
thats an old cheap motorcyle trick
or pull them off adn take to a machine shop and have em checked
a friend that has a shop with a turning machine, checks every new rotor before mounting

[FreedS4]

yes
if you have a harbor freight near you you can get a dial indicator adn stand for under 30 bucks, and you can check if the rotors are warped on the car
you can also do it with a sharpie, a vice grip a c clamp adn a chair. set the sharpie in the vice grip and clamp to the chair. move the chair so it is a papers thickness away from the rotor, spin the rotor, see if you get any marks on the rotor, if you do, its probablly warped
thats an old cheap motorcyle trick
or pull them off adn take to a machine shop and have em checked
a friend that has a shop with a turning machine, checks every new rotor before mounting

Good stuff, thank you. I went ahead and ordered a new rotor from patrick at BMA. He didn't seem to think it was a rotor issue, but we'll see after I install it.

[dude8383]

chances are it was indeed a warped rotor, the last time i replaced my rotors the fronts were warped.

[FreedS4]

chances are it was indeed a warped rotor, the last time i replaced my rotors the fronts were warped.

Let's hope that that was indeed the issue. I should get it on Saturday and it's going on as soon as it gets here.