long time lurker first time poster...

i have a 98 4 dr auto and a couple of days ago i noticed what sounded like a metal on metal squeal while accelerating, reversing or coasting. i know i need to replace my brakepads soon but the sound goes away under braking. i was wondering if this was some kind of early warning indication to replace the brakes or if i had a different problem. has anybody experienced this before?

thanks in advance