Toyota Repair: 96 corolla chirping, front wheel bearings, corolla wagon

Question
The car is a 1996 Corolla Wagon with 44000 miles and  automatic.  I have had it a few months.

Since shortly after I bought it, there has been a chirping or a squeaking sound that appears to come from the front wheels.  I bought it on a rainy day and didn't notice the squeak.  It appeared as I drove it home and became quite loud. You can clearly hear it with the windows shut.  The sound seems to occur once per rotation of the wheels. It definitely depends on wheel speed, not engine speed.

The sound does not change or diminish when I apply the brakes, so I don't think it is brake related.

It is quieter when you first start out (first few tenths of a mile) then gets louder.

There is no play in the steering, and I've had no problems with tracking. There has also been no problems with fuel economy .

Any ideas?  

Answer
Either one of two things, the brake pads are low and the sensors are touching the rotors or there is a problem with the front wheel bearings, try to remove the cotter pin from the front axle nut and try to tighten the 30mm axle nut to about 200ft/lbs with a torque wrench and see if the noise goes away, if not the axle bearings and hubs need to be replaced.