McGyver

When I apply the brakes hard in these conditions, I hear an unpleasant grinding coming from the front brakes and it feels like I'm rolling over a bucket of gravel. Anyone else?

I mentioned this to Audi at my 5k mile maintenance visit, but they indicated that everything was okay. TIA for your help.

daveak05

You ARE rolling over a "bucket" of gravel : ) ...sounds like UR just crunching debri w/tires

craiglieberman

Its possible that you could've picked up a small piece of debris that has lodged between the pad and the rotor, although it is unlikely.

If the front wheel bearings and suspension show no signs of missing bolts, I can't imagine what the sound could be...so hard to diagnose from behind a keyboard, you know?

daveak05

Good point, but the clincher here is "when he's driving over wet and dirty surfaces"

McGyver

I may have to do a ride-along with the maintenance guy.

McGyver

Correct. I've done a few 90-0 hard stops (on dry) with a firm/quiet response.

bpp

pad materiel onto the rotor. If so, it will wear off over the next few miles with normal driving and light brake applications. The rotors in this case are okay, it's just that you've created a rough surface temporarily from the transfer of pad materiel. What's happened is the resin friction binders have melted from the heat of the high-speed stops. 90-10 is good with some cooling time, maybe 1/4-1/2 mile between applications. If you STOPPED from 90 and did it again, the pads are against the rotor at rest and not a good thing when very hot (1000 F.). But, you probably already know this.
Can't figure in the wet & dirty surface aspect though.

McGyver

Thanks.

bpp

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