Boy, if your going to jack on the frame you better do it very near the axel. And, then your going to have to go up a long ways to get the tire far enough off the ground. If you figure the flat tire is down 3 inches from where it would be totally inflated and that you have 3 inches of axel movement you are going to have to raise the frame 8 inches to get the flat tire off the ground far enough to get the new one back on. And, I don't get the drive the other wheel up on a block thing. With my spring axles that are hooked together in the middle that isn't going to accomplish anything.