Chris,

What exactly do they mean by the "bellows"? If your motor is vibrating, I would think it would be an imbalanced shaft (cage). The cage does have little weights on it for balance. I just installed mine (Behr with cage) and it operates smoothly as ever. The only flap in that area is the recirculation flap. If the bellows (or air flaps) are not opening, It wont cause a vibration.

-Andy

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