I’m in the same situation you’re in. I have a 2008 Chevy Silverado 1500 and I have a constant humming and it becomes louder as I gain speed and it quiets down when I’m coasting but the humming is still there. I have replaced the front wheel bearings, brakes and all tires and still no luck. Any suggestions?

 

ouch. it's crying out in pain. You probably want to check the rear end and stop driving it.