Trust me ... this really isn't off topic.
Your Lab sounds a lot like our cats when it comes to traveling. "Most" cats are wildly adverse to getting in a vehicle of any type and then moving down the road. As has been explained to me numerous times over the years, cats just can't focus on fast moving scenery from a vehicle so they get confused/scared and start screaming. That was true with our three until we started traveling in the MH. When we're under way, each goes to the back (where the shades are down) or stays on the floor and they relax. The actual movement of the coach doesn't bother them and they don't even try to look out any of the windows. They're quiet and we're happy.
As soon as we stop, for whatever reason, they're up and wandering all over the coach - on the dash - looking out the window, etc. Break's over, put the MH in gear and PRESTO the cats disappear!
As everyone else has mentioned, when we leave for any period, the vent fans are left open with the thermostat set to turn on at a very low setting in case the A/C fails. We don't worry so much about them barking at neighbors so the curtains and drapes are left open enough for them to entertain themselves looking outside.