i have a 02 z, and when im cruising around 30-40,and i let foot off the pedal, i can feel something rubbing feeling and sound under the driver side floor(right under my foot), and when im looking for parking (i.e.), i can hear rubbing noises...what are those sounds and are they related???

02 z, a4 flowpac, 3200 vig., 3.73. lca, magnaflo, cutout

 

May have to grease you lca and rest of the suspension bushings it's a start.