Sounds like the the bearing to me by your description. A couple ways to nail it down.
First have the codes pulled from the computer, good chance it will point to the problem child or children if both are a problem.
Second, it too raise the front end so the wheels are off the ground, run the motor until the speedometer hit 30 mph and hold it. You may be able to hear which wheel is the noisy one. May need a stethoscope and may need to prevent one wheel at a time from spinning while checking this.
My preference is a Timken brand wheel bearing/hub assembly.
Here is a video for the style of repair
Monday, February 5th, 2007 AT 5:16 PM