Hello,

I have a 2001 S4 with a few mods but nothing crazy. The car has newer rotors and pads with less than 20000 miles on them. There is a pulsation coming from the front driver-side when I hit the brakes.

The funny thing is that this was completely fine yesterday and all of a sudden there is a major pulsation like the rotor is completely warped but that couldn't happen over night. Its like something broke or snapped. I don't think it is the ABS sensor because the pulsation is more like a dud-dud-dud-dud-dud rather than a grinding ABS noise.

I did a visual inspection and everything seems fine, I also cleaned the brake assembly with brake cleaner but no good news.

So, any chance anyone ran into a similiar problem?

Thanks,
RCF

 

does the dud-dud-dud-dud-dud occur even when your not on the brakes?

does the dud-dud-dud-dud-dud change with speed?

I'm leading to a possible bearing gone bad...

Shawn

 

That bearing assembly (the entire axle) was just replaced less then 10K miles ago.

The dud-dud-dud happens only when applying the brakes moderate to hard.

Like i said, this just started this morning, damn car was absolutely fine the night before. [:@]

 

alot can happen to the front brakes in 20,000 miles..... i would re-check all bolts to make sure they are at specified torque and change/re-bleedthe brake fluid if that has not been changed...

 

Any other suggestions out there before I disassble and reassemble this brake assembly?

 

Just try to rebed the pads. You might have some build up on them.

You find a nice road where you can go up to 60 & brake hard a few times, then do a couple moderate stops, then drive around to cool them off.

 

Fair enough... I did already try the braking technique but that didn't work. However, I will reseat the pads and etc.