To roll back, follow the Steam Beta instructions above. Drive safely, and keep the rubber on the road.
Version 1.38 is useless without mods for most veteran players. Here is how to find and install compatible mods. Download Euro Truck Simulator 2 1.38
If you already own the game on Steam, you do not need to "download" a separate installer; you simply switch your current installation to the 1.38 branch: Open Steam and go to your Right-click Euro Truck Simulator 2 and select Properties Navigate to the tab on the left sidebar. To roll back, follow the Steam Beta instructions above