Is this normal for an AF Nikkor 70-300mm lens?

Last week I bought a used AF Nikkor 70-300mm 1:4-5.6G lens from Adorama. It arrived today, and while it seems to be in great condition with only a few cosmetic blemishes I've noticed that when adjusting the focus manually it makes a sort of whirring/grinding noise. I'm not talking about the noise the autofocus motor makes; I was expecting that to be louder than my AF-S kit lens. Is this typical operation for this lens, or should I send it back for a replacement?