Lift amount does NOT equal spacer thickness owing to the suspension geometry. Lift spacer is not equal to the actual spacer thickness. *****Rear Block is 1.5" thickness 2004-2020 2WD has NO stock block, if remove your stock block, it will provide additional 1.5" lift. 2004-2008 4WD has 2" stock block, if remove your stock block, it will provide NO additional lift. 2009-2020 4WD has 1.5" stock block, if remove your stock block, it will provide NO additional lift. What is a leveling kit? .