Humming coming from my 01 Boxster, any suggestions on what to look for

[Jasper7821]

Did the test and it is not coming from the front, turning the wheel at speed both ways made no difference.

Originally Posted by Gilles

+ 1 on a wheel bearing.

If you can find a long downhill street (w/little traffic..) turn off the engine and let it roll :-)

While going downhill turn to the Right and see if the noise increases or goes away, if increases then it will be your left side bearing, and if you turn Left and the noise increases then would be the right side bearing.

Regardless, with the mileage you should replace them at once as the other ones are right behind.. The bearings are easy to replace but it's a bear of a job to do it (physically)..