Hey you guys are really funny...

maybe a noob question, but it would seem to me that if the weight fell off, that it would be more in the steering wheel wouldnt it? idk im new to everything that isnt the motor. had a problem like that once but let my buddy borrow my 95 SC2 and it came back and above 40 it shook the wheel damn near out of my hand, got under it and turn out there was 2 inches of hardened mud caked on the inside, so thats where the thought came from. correct me if im wrong

Mr.SC2 --

You had the experience of what could be best described as 'dramatically out of balance' and the vehicle responded accordingly. My suggestion initially ignored the missing wheel weight, because there's no way to be sure when it fell off.

On today's roads with their high crown centers, alignment of tires is critical, and a bad alignment can lead to uneven wear, creating noise/whining/etc. I still think he needs to make sure of his alignment, then swap (or replace) tire(s) as necessary to fix the problem ...(in my opinion)

update
 

it was a wheel bearing on the front drivers side wheel

I win (well, half -- I guessed the wrong wheel)

Winner's Reward
 

Ok, ok -- my hat is off to Derf on this diagnosis. Way to go.....