Let me ask this . If u set shocks to zero rebound building them ,I'm thiking this pulls a vacume once shocks r installed on car since they r sitting with about 7-9mm of shock shaft showing . With that being said , if a person was to build the shocks with 7-9mm of shaft showing so when car is sitting at ride height their is no pressure or vacume inside the shocks . Is their a reason this isn't the preferred way to build any shock . I built my photon shocks like this and I never "never" had to rebuild shock cause of them having air in them ....