THIS
Currently unavailable on Amazon. They're selling one called "Strongway" and this pic is a "Torin" brand. I show it to illustrate its DOUBLE RAM feature. Most Bottle Jacks are Standard or Shorty. A Standard may not fit under your axle when a tire is flat. A Shorty will fit, but may not lift high enough to mount your inflated spare. A Double Ram, starts out Shorty but lifts as high as Standard because the ram telescopes out. Price is nearly double a Shorty or Standard, but it's sure to do your job.
12-ton isn't because a Class C weighs 12 tons. More like 7 tons max and you are lifting more or less a corner of it. The problem is, the jack has to work in an awkward location, under the coach. All that reserve capacity makes the jack easy enough to operate, that you can actually raise the coach from under there.
You also need blocks or a jack stand to support it. If you have an OEM lug wrench, get an extension pipe. If you don't have one, a 20-some-inch "Four Way" meant for trucks not cars, will get you through a roadside tire change. If you have a Ford, torque is "only" 140-ft-lb.
