I had an interesting day...
To start, I've been hearing and feeling this grinding/humming noise coming from the front end, so I suspect a wheel bearing. Yesterday, while I was topping it up with the only ethanol-free gas in the area ($3.59/gal) I push on the top of both front tires, and sure enough, the drivers side wobbles back and forth. Crap. So, being the piss poor broke bloke that I am, I stop by the pick-n-pull on my way home from work and pull the bearing off the truck with the lowest miles (blown engine 1997 Tahoe with 87,000 miles, sad) to swap it out. I'm going to sas it anyway so all it needs to do is last until this fall.
I get home, jack it up, and I notice the lugnuts are pretty loose!! what the @#$%? (I had Les Scwab rotate the tires a few days ago...) and just out of morbid fear and curiousity, I check all the others, sure enough, they're ALL loose. Dumbass didn't torque them, this WILL go on his record. Anyways, I go on a test drive to see if that was the issue, and it wasn't. Now I'm puzzled. I crawl under it and start pushing and pulling on everything I can, and discover the bearing on the driver side output on the differential is shot. Whew! dodged a bullet there, at least that one is not load bearing. However, it is leaking (explains why it won't stay sealed...) as well as the t-case front output, again, which the slip-yoke on that is showing play now...
It never ends... October can't come soon enough.