a body lift lifts the frame higher on the body, allowing better rocker panel to rocks clearance, and allows you to run bigger tires. a suspension lift actually raises the entire truck through installment of new 4x4 parts. IFS lifts are worthless in my mind, because IFS is inherently weak. id always go with a solid front axle lift
a body lift ia actually what it says it is.....it just lifts the body off the frame. you lift it up and stick some pucks between the body and the frame at the mounting points and you have a body that is lifted.