Fear of Driving to the Mountains

First thing you need to do is get some experience on much shorter drives that aren't so challenging. Driving a car up or down a steep grade uses the same basic principles. Use the correct gear and brake correctly. I've towed good sized boats up to Big Bear a bunch and I've never had to drop into first gear. Lots of RV'ers go up there. Consider taking the route you're planning to take in your car first. Wait for an RV and (safely) follow them. But you really should start with something shorter and not so steep.