Bumping an old thread, I am starting to hear a humming noise that sounds like it's coming from the front. But in my case its 0-40mph speed dependent. Cruising on the highway, I do not hear it at all. Accelerating to 40 its an increased hum, and decelerating from 40 its a decreased hum.

I'll try and measure the tire trend depth first and report back.

My initial thoughts were:
Tires
Something rubbing
Slight wheel bend
Alignment issue.

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2004 BMW M3 Individual
2009 BMW E70 X5 35d
2011 BMW E70 X5 35d - Totaled
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