1/2 ton pickup + 6000 lb TT on 5000 mi western trip

Just to add to Old-Biscuit's comments - do some route planning.

There's often more than one way to get to a place. Pre-planning may let you bypass some of the grades. For example, there are a few ways to go between Cody, WY and Rapid City, SD. Some routes have more steep grades than others. A little research can save some stress.

Take your time, follow the advice from the others, and I'd guess you'll be just fine.