Do you carry a jack? If so what kind.

Desert Captain wrote:
Something else to be considered while we discuss jacks...

Do you have a safety jack stand or are you willing to bet your life on the jack alone? I will not crawl under any vehicle that is lifted-supported by just a jack. If it fails and you are underneath the rig bad things are going to happen quickly.

While rare, jacks do fail, had a 6 ton model that jacked the coach up just fine and then immediately began to slip back down {a seal had dried out and was leaking hydraulic fluid}. My new jack is an 8 ton bottle style.

There's no need to crawl under the vehicle while it's supported by the jack when changing a tire, so jack stands are unnecessary for that particular case. Still, the advice to never do so is spot-on. At least my motorhome has sufficient clearance underneath for me to crawl around relatively easily without jacking it up. My Honda Fit is quite a different matter.

Lacking a jack stand, properly laid up cribbing is a viable alternative. (It's worth noting that many jack stand weight ratings are per pair. A set of six ton jack stands are usually rated at three tons apiece and would be marginal or insufficient for the back axle of many class C's.)