Re: wheel bearings...
Now that I have my snows on I'll have to listen carefully. My ride to work was much quieter...and that got me thinking. I've had these snow tires since November of '08. That's 3 full winters plus the winter the previous owner put on them. They show wear on the inside and minor cupping, but nothing nearly as bad as the summer tires. I thought for a moment that perhaps the summer rims were just not balanced properly, but both left and right tires show the same wear. If they are unbalanced, it is likely the result and not the cause. Ehh, I guess I'm just talking myself in circles.
Anyway, back to the bearings. I didn't hear any howling on the highway this morning other than the typical hum of the snow tires. I do however have an odd sound that occurs the first few miles I drive. It's a creaking/grinding sound that occurs when I lift off, or apply throttle (ie when I shift gears or tap the throttle to shift the weight of the car). It's the kind of sound you might hear as you sit down on an old chair, then get up again. I have a suspicion that it is in the transfer case. My ears say it is coming from the right side of the engine bay. It does not make the sound when I coast over speed bumps so I think I have ruled out suspension bushings / ball joints. I can reproduce the sound clear as day when the car is cold, but 10 miles down the road it is gone. I've checked the fluid level in the transfer case and it is plenty full, so I'm not sure what is going on.