My blower motor began to make noise off and on about 2 months ago, and it seems that the noises are getting worse when they happen. It is not a constant thing. I am assuming this means my blower motor is on its last legs. How long do they usually last when they start making noise? Is it a short term thing, like a few months, or could it potentially last a year? I am trying to decided if I should replace it soon or wait until it actually dies. Time is the real issue, and I don't want it to die when i am so busy i can't do anything about it.