I believe Expeditions was changed to be a bit simpler or more friendly to new players. I read somewhere that the physics were changed and one thing you can visibly see is the body flex on the trucks is significantly reduced or completely removed in Expeditions.
I think of Expeditions like a spinoff game, where Spintires/Mudrunner and Snowrunner are main games. Like Forza Motorsport vs Forza Horizon.