i've got a 97 2.0ltr non turbo impreza with a really annoying high pitch squeal. doesn't happen for about the first ten minutes of driving then just appears it does it for as long as i can hear it over the exhaust and until i come to a complete stop the noise doesn't vairy what ever speed im doing just a constant noise. i've changed the brakes and chech the wheel bearings for any play i've also checked the rear diff oil and the gearbox oil i dont think it is engine noise as i have turned the engine off and just let it roll and the noise is still there any ideas anyone