Yes spacers were essential as it does rub without. No vibrations noted however..rides great. Studs plenty long. Was a little bothered by having to run spacers but got such a good price on wheels i got over it. BTW I think I saw where EBay had same price listed for what I got for...$790 to my door. Also read somewhere where an installer grounded calipers down ALOT after buying and researching/disecting an oem caliper and had no ill effects. Forgot where I read this. Hope this helps.