My 2002 Grand Prix sounds fine upon starting. When I get to 45 mph, it starts to sound as if it's working harder. It's like a loud hum starts and gets louder as it goes up to 60 mph. As I decrease speed, the hum also decreases. I don't think it's there at all much below 45.

Front Wheel Bearing Hub

You will have to remove the brake calipers,hang it,&
remove the rotor,then you can turn the hub & feel the
roughness.

ROCK AUTO.com for parts & look at that hub, so you
match it up the same. Don't get in love with one brand
you like, if the hub looks different at the back where the
speed sensor goes in

You also may find your self buying a torx socket or metric
socket driver to get the speed sensor out. Maybe not

If tools are needed,do yourself a favor & step inside a Snap-On
Truck & just buy one item or so. If you don't ,you won't find those
items anywhere