New Shocks with Leaf Pack?

I am running a Procomp 3" lift/level kit on my 2006 DC/OR which consists of the shock spacer in the front and AAL springs in the rear to achieve 3" of lift. everything else is OEM (shocks, springs) The OEM leaf springs are sagging and I want to replace them(and the AAL) with All Pro Expedition leaf packs which claim 3" of lift. All Pro is telling me that I will need to replace the OEM shocks because they will be too short. Why would they be too short? Shouldn't my ride height remain the same?

 

Your ride height will be slightly higher with AP expos. But in any case ur shocks are to short anyway righ now. They may be working fine on road but off road u prolly dont have much droop.