hum

Was dark & pouring rain so doing more road test tomorrow but figured would see if anyone has dealt with this problem because I know something is going to need to be fixed. 2003 Tahoe LT (250k on 5.3\4x4\3:73) when driving in Ax4 rigs developed a slight vibration (can only be felt in pedals &...

2005 Tahoe Z71: I've noticed a noise from under the truck when I use the Auto 4WD button and decelerate or coast to a stop. (I have 4 buttons: Auto 4WD, 2WD, 4HI, 4L) It resembles the noise or hum of knobby tires on a smooth paved surface. Putting it back to 2WD eliminates the noise. Any...