The instructions that came with my 5ver when new say to only jack the rig up using the frame rails. However, I have jacked the wheel off the ground by placing my bottle jack directly under the flat plate that's under the axle right behind the wheel with no issues. You done have to jack it as high that way. Using the frame rails requires and extraordinary amount of lift to get the wheel off the ground high enough to get the new tire and rim on. I also have a 1/2" thick steel plate about 5" in diameter that I place under the axle plate to help distribute the pressure on the axle plate.