While ETS2 received map updates, its sister game ATS received specific truck chassis updates that often get ported via mod packs:

: Ensure your mod version is specifically tagged for 1.40+. Versions designed for 1.39 or older will have broken headlights and flat textures due to the lighting engine change.

The for Euro Truck Simulator 2 (ETS2) was a transformative release that introduced a ground-breaking visual lighting system and significant map overhauls. While the core "American Truck Pack" refers to a popular community mod that ports American Truck Simulator (ATS) vehicles into ETS2, the 1.40 update itself changed how these trucks looked and functioned due to the new engine-level graphics. The Game-Changer: New Visual Lighting System

: For those using an "American Truck Pack" mod, 1.40 was a critical turning point. Because of the new lighting, older modded trucks often appeared "blown out" or too dark until their materials were updated to support the new system. Map Reworks: Germany and France

: Large portions of the German road network were completely rebuilt with modern assets and realistic junctions.

If you are looking to drive American trucks in ETS2 1.40, you generally need a "Truck Conversion" mod.

The most significant part of the SCS Software 1.40 Update was the complete revamp of the lighting system.

: Support for 4x2, 8x4, and 8x6 chassis configurations was introduced, allowing for heavy-haul setups on American rigs like the Western Star 49X.