Good to hear you found an answer. My first motorhome was a Tiffin Allegro with a P30 chassis and it always had a lot of blowback from Trucks, though it was better after i replaced the air bags. The worst problem was being passed by Honda cars and SUV's .....I never figured out if their view of the road made them drive closer when passing or if the shape just gave them more unstable air and thus more turbulence and pushback for you. Hondas are the only thing close to a Flxible bus for pushback.
Yes, i have my Nomex on.....I know the Honda owners are going to s--t on me full-time for saying that.
