The stock linkage is attached to the tub at one end and the TC at the other. When you raise the body with a body lift, the tub side gets put in a bind since only one side is moving, so problems with shifting could happen. Personally, I've never had much of a problem with my stock TC linkage even when I lowered my TC skid down 1", or after I installed my baby body lift, but the bigger BL's sometimes create an issue.