Hy Delux, Everything is just a little bit larger on those big boys. The tire/wheel combo probably weighs 100+ lbs. depending on the size. I think you are right about the brake light switch being stuck, some Internationals I've worked on have had hydraulic brake light switches, but you'll have to check yours out and see whether it's a mechanical or hydraulic. If you post the year and model we can probably come up with some numbers and advice for you, hope that helps.