Dude i didnt even notice that you had alcans.... you shouldnt have vibration. I have had two sets of alcans and the only reason I had vibrations (very slight) with the first set was because I was useing shackles in conjunction with them. Now i dont have a problem with my second set.Scott said:I have the famous driveline vibration from putting a new (lifted) spring pack in. I ordered the 2 degree shims from AC. Do I need to get new center pins too? How much center pin needs to stick into the axle to be safe?