I was hearing a humming in the right rear of my 2003 Montan AWD with
200k miles, wrapped up a split in the muffler, replaced a wheel
bearing, got new tires, noise is unchanged. It drives fine otherwise.
There is a very slight clunk/click when starting off, so I'm thinking
it's the drive train. I've also replaced both rear upper control arm
bushings. It's proportionate to vehicle speed (not motor speed),
changes slightly when cornering.
Any ideas? Any idea how hard to fix?