High Pitched Noise

I've recently developed a noise in my 88 325i, I noticed it after I took the car to a Car-wash where I used the spray wand, co-incidence I believe ?
At about 15-20 mph I'll hear a high pitched whine coming from the left rear wheel hub, goes away when you slow to 20 or so. Friends and I isolated the noise while the car was on a lift with the wheel off, the noise sounds like it is coming in contact with rubber. I took off the axle nut, pushed the axle in a bit, to lube behind the hub thinking that would alleviate the issue, not so. Any thoughts as to what is causing the noise. Auto tranny fyi

wheel bearing

I agree with Downhiller
This tool of destruction, you mentioned as a

spray wand

should be prohibited
So should Oxy Acetalene torches.

You managed to destroy the wheelbearing seal with this

spray wand

You are not the first !

+1

Noise went from consistent to inconsistent to gone, over the course of 5 days, variety of drive lengths, speed so forth, no bearing roughness or growl. ??

if its gone dont worry about it. probably rusted something or got some sand where it shouldnt of been and finally worked its way out

And the Winner is Downhiller, heard the rumble Thursday, confirmed a failing left rear wheelbearing.