After being underneath the car, and doing some checks, I think my wheel bearings might be bad. I had the rear of the car supported on ramps, and I physically shook the car side to side, and noticed a rattle/clunking sound. With the car on the ground, I grabbed the wheel and shook, and reproduced this same clunking sound. It feels like there is slop in the wheel. Are these valid symptoms of a bad wheel bearing? Is this a complicated part to replace, aside from the astronomical torque needed to remove the spindle nut? Should I let a shop do it, or try it myself?

 

A wheel bearing will produce a kind of humming noise when your driving on the highway when it starts to go.

 

Haven't noticed this humming noise, although it may be muffled by the road noise, and other various shakes and rattles from within the car at speed...

 

I do notice a shimmy/vibration in the steering wheel when slowing down, from above 40-50mph. Could this be related?