If the blower motor is vibrating, I would start by removing it. I have seen cases where the rodent met it's maker at the blower fan, and that is what was causing the imbalance(vibration). They also may have built a nest that ended up at the blower. As far as cleaning the vents, that could be labor intensive, as there is no easy way other than complete disassembly.
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Saturday, July 16th, 2011 AT 3:47 PM