Front brakes pulsation when applied

[SDS135]

When I brake my front brakes pulse/stutter (in the steering wheel mostly but also the pedal). I notice it when braking from 80km/h+. I don't notice any issues when driving, no matter what speed.

I installed Genuine BMW performance rotors (slotted/cross drilled) about 30000km ago. I do a lot of highway KMs so I don't brake too much (there is no lip on them from use, yet).

I notice when I turn the car on in the morning and start moving the brakes always make a noise. Like they were stuck to the pad. The car sat in an underground garage for less than 12h since driven last.

I know about warped rotors but would really be surprised. Car is under warranty, and I could try to prove a case about the calliper sticking.

Advice is appreciated.

[Kgolf31]

Did you properly bed the pads to the rotors when you first installed them?

Warping rotors is VERY unlikely.

[SDS135]

Originally Posted by Kgolf31

Did you properly bed the pads to the rotors when you first installed them?

Warping rotors is VERY unlikely.

Yeah after install they were amazing! I've done brakes many times before and had help as well. After install they were very smooth.

Honestly I just noticed this issues when I picked up the car from some warranty work. Before dropping it off at the dealer I didn't notice anything.

[SDS135]

Second thing is the car was sitting at the dealer for a week before they even got to doing the injectors warranty work (outside in the winter weather).

And couple this with a caliper seizing issues...

[Kgolf31]

Originally Posted by SDS135

Second thing is the car was sitting at the dealer for a week before they even got to doing the injectors warranty work (outside in the winter weather).

And couple this with a caliper seizing issues...

If you have caliper seizing issues, you probably had pad deposits on the rotor itself.

Go back and re-bed to see if the issues are reduced.

[MightyMouseTech]

If it was sitting outside for a week in Ontario weather the past week, it is rust on the rotors. Rain, high humidity, high salt use combined with just above freezing temperatures is the perfect recipe for highly corroded rotors.

[SDS135]

Originally Posted by MightyMouseTech

If it was sitting outside for a week in Ontario weather the past week, it is rust on the rotors. Rain, high humidity, high salt use combined with just above freezing temperatures is the perfect recipe for highly corroded rotors.

Exactly! And honestly I haven't put a lot of kms since I got the car. So I may not have removed it all. Plus is snowing like crazy right now.

Should normal driving and braking fix the issue?

[MightyMouseTech]

Some heavy braking may or may not clean it off. They may require machining to get them smooth again.

[SDS135]

Been working the brakes. Not extremely hard but slowing down from 140-150kmh and they are back to normal... Seems like it was just a weathering issue.

Dealer wanted me to bring the car in right away to replace rotors and pads...