I have extremely limited experience on mountain roads or long grades and none at all in anything other than a passenger vehicle.
* I was westbound on I-70 west of Denver and extremely low on fuel. Unfamiliar with the area, I had missed the last exit with gas and found myself facing several miles before the next. Luckily, as it turned out, that section was all downhill, through the Eisenhower Tunnel and with no significant traffic that might have led to stopping and waiting. I almost coasted off the next ramp (probably Silverthorne) and into the gas station.
* I was westbound on I-40 in a full sized Dodge van that was completely empty when I got into very high winds in NM. Not a pleasant ride either.
* I was eastbound on I-94 east of Benton Harbor and came into high winds. I was in a little car, but the semi in front of me went over to nearly 45 degrees before passing some trees that blocked the wind, allowing it to right itself and continue on.
* I was westbound on I-96 in Detroit when a stake truck blew a tire, started to go over and dumped much of a load of metal castings (something like unfinished U joints) all over the road.