Hey Sean,
You helped bring up tons of memories. Old Route 66? Highway 44 down south somewhere, etc. The run from Michigan all the way down to Miami. Long summer hauls from Illinois to The Black Hills and nearby areas.
As an eight year old kid I took those trips with my parents and sibs as you described so well. Then as a married man my father in law insisted we pile into his Winnebago, then later his big GMC for 'out West' trips, lots of camping. Um, I was his official 'crap chief', yep, I emptied out the damn septic tanks every morning and hosed it all down!
Yeah, so sorry, just couldn't resist!
Lot's of fun.
Tom