new brakes stuttering when stopping

[haudi4]

Hey all,

I just replaced my front rotors and pads and as soon as i started driving i noticed that once the car comes to a full stop the brakes seem to stutter and then stop. I can see the rotor spin even after the wheel stops for just a split second. What could it be? I was sure to take my time so i'm sure i didn't miss anything...

[BryMFL]

I would say you may have some air in the lines or With new pads and rotors it may have to readjust itself.

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[Rausch]

Did you bed the brakes in correctly? Maybe you got some contaminants on the pad such as grease. What brand of pads did you use?

[Spike00513]

Hey all,

I just replaced my front rotors and pads and as soon as i started driving i noticed that once the car comes to a full stop the brakes seem to stutter and then stop. I can see the rotor spin even after the wheel stops for just a split second. What could it be? I was sure to take my time so i'm sure i didn't miss anything...

That I don't understand, because the rotor and wheel and disc are supposed to move together, as one unit, because they become sandwiched together on the hub once you install the 5 lug bolts.

Imagine removing a wheel from a car, and gluing a rotor to the back of it. They move as one, together.
Theoretical glue.
Elmer's glue will not bond heavy metal parts like this, in real life.

Did you bed the brakes in correctly? Maybe you got some contaminants on the pad such as grease. What brand of pads did you use?

Wonder if there's a way to remove contaminants. I think once my pads were glazed so I sanded them. Another time I had the area taken apart for a separate reason, and the pad was half worn so I thought about re-chamfering the edges while I was in there, but I'm not sure if my file tools are strong enough. I guess another time I got some grease on it, and heard that boiling water will remove it. I used a whole tea-kettle. Then brake cleaner. BUT, pads are said to be absorbent like sponges. So maybe care should be taken? For example, installing a wet pad on a car that sits. It will rust the rotor in that spot.

I have to be very careful when lubing the system. Not sure if my method is correct, but so far I've done:

- NAPA Sil-Glyde for the caliper guide pins
- clean hub mating surfaces with 3M roloc
- try to clean lug bolts with wire brush
- thin coat of anti-sieze on hub mating surfaces (wheel, hub, etc.)
- CRC Disc Brake Quiet paste on the back of pads
- CRC Brake Grease (dark grey color) on pad ears and carrier grooves (machined metal) so that it slides freely
- Brake Cleaner on the disc when new, to remove the factory thin film of oil that keeps it from corroding while sitting on a warehouse shelf open to possibly-humid atmosphere

[audireme]

Are the wheel lugs properly torqued down? Maybe if you were using a brake cleaner, some dirt got washed off and got to the ABS sensor.

[haudi4]

Did you bed the brakes in correctly? Maybe you got some contaminants on the pad such as grease. What brand of pads did you use?

i used powerstop brakes. I'll disassemble them in the morning and check, do you recommend i sand the pads a little bit?

[haudi4]

Are the wheel lugs properly torqued down? Maybe if you were using a brake cleaner, some dirt got washed off and got to the ABS sensor.

i used brake cleaner only when the parts were disassembled and not while they were on the hub so i don't think i got any into the sensor. I'll make sure the lugs are torqued enough

[haudi4]

Yeah i might have just been imagining it because it doesn't make sense to me either lol.

- - - Updated - - -

Yeah i might have just been imagining it because it doesn't make sense to me either lol.

@spike00513

[BryMFL]

If the rotors are spinning the lugs are not tight or they are tight prematurely.

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[Spike00513]

Are the wheel lugs properly torqued down? Maybe if you were using a brake cleaner, some dirt got washed off and got to the ABS sensor.

Isn't that sensor a magnet too?

Speaking of wheel lugs, despite running mine through a wire brush AND 'thread restorer kit', they still don't look good.
The cheapest I found for new replacements was on FCP.

https://www.fcpeuro.com/products/aud...febi-wht002437

[audireme]

Isn't that sensor a magnet too?

Speaking of wheel lugs, despite running mine through a wire brush AND 'thread restorer kit', they still don't look good.
The cheapest I found for new replacements was on FCP.

Yes, it is. When dirt gets between the sensor and CV joint ring it can act up.

For the lugs, I coat mine with an anti-seize lubricant, just lightly with a small brush. I know there are posts out there strongly advising against it, but I never had a single bolt come loose. Always torqued at 90 ft-lbs. I've been doing it for years on all of my cars, keeps them rust free.

[haudi4]

Good news, after a few hard stops without fully stopping, the brakes don't stutter anymore! However when I look at the pads on both front sides, they don't seem to be fully touching the rotor. Is this normal for brand new pads? They're carbon ceramic


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[Rausch]

Some pads come chamfered at the edges. Totally normal.

[audireme]

Good news, after a few hard stops without fully stopping, the brakes don't stutter anymore! However when I look at the pads on both front sides, they don't seem to be fully touching the rotor. Is this normal for brand new pads?

You wouldn't want them to be touching the rotors if you don't apply the brakes. As Rausch said, those pads look fine.

[MacFady]

As someone else asked, did you do a full bed in procedure or just a couple hard stops? Doing a proper bedding in will really improve the feel and performance of brand new hardware.

[A4SoftWalker]

Click here and become a bit more educated on the subject of brakes in general and brake bedding in particular.

And here

And here

And finally here

[haudi4]

Click here and become a bit more educated on the subject of brakes in general and brake bedding in particular.

And here

And here

And finally here

Thanks for this! I will perform the full bed-in procedure tonight when the city streets are a bit emptier lol


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[A4SoftWalker]

Thanks for this! I will perform the full bed-in procedure tonight when the city streets are a bit emptier lol


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^^^That or on the weekend I go to one of the many empty business parks around here. Glad you found the info useful. Have a print out with you in case a cop decides they're bored. Might get you out of trouble or not. Worked for me.