I have a similar problem with my 2003 malibu
it increased so much after I had it washed with oil below the chasis,
a gentle touch to the brake starts an intermittent sound which disappears with increased pressing on the brake.
also a roaring sound is there..
Roaring sound decresed after I have turned the front wheels to the back and those on the back to the front .
but another sound started to appear at a speed of 80 km
I dont what's the source of the sound.
Have found the answer ??
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