Ok, so my passenger window has been making a cracking noise only when I put it up (only makes the noise when the window gets about 3/4 of the way up). My question is, if it is indeed my regulator going bad, how long on average does it take before it stops working altogether? I don't want to replace it if the noise is nothing, beacuse this has been going on for about 3+ months now. Any ideas? Thanks!