1st I'd verify my actual height when hooked up. 2nd I'd buy a truckers atlas from a local truck stop they are around $20 and they even have a large print addition and a plastic coated page version for around $50 you can grease pencil on and they last for years.
I'm about 12'6" (new A/C unit need to re-measure)and my "normal ride" is 13'6". Clearance is often an issue in the eastern part of the country. Some states like NY mark their bridges a foot low so it you hit it it's your fault. Unless it says "ACTUAL" then it really is what it says. Confused yet?
When you look at a trucker's map the truck routes are highlighted. There is a list of low clearances by state and route in the front of the book. There is also a list of weight limited bridges.
Running from the coast to coast I often took the US roads to see more of the country instead of being on bypass mode. By all means go explore but a little common sense goes a long way. We don't want to see you on YouTube ;)
