1999 Chevy Silverado 5.3L V8
Air filter has been replaced since buzzing started. No result.
Question = I have a 1999 Silverado. Whenever the AC or Heater is
turned on the fan buzzes loudly, and the buzzing gets louder as the
air is turned up. It still produces air/heat but it's very loud and may
lead to a failure eventually. Is this a problem with the blower motor?
Does it need to be replaced?
Most likely what you are experiencing with your Silverado is either
debris inside the heater case that is contacting the blower motor as it
spins, or just a faulty blower motor. Sometimes a piece of paper or
trash gets sucked into the area where the blower motor is mounted
and it hits the plastic fan blade and makes a buzzing sound. It's even
possible that something from the glove box made it's way into the
wrong place. I've pulled anything from wrappers, straws, envelopes,
and napkins from inside the blower motor housing before, so anything
is possible. I would recommend removing the blower motor to check
for debris. If none is found, inspect the fan for any broken pieces or
being out of round. Replace as necessary.