While there is no single official "patched" mod specifically titled "400 km/h," achieving extreme speeds in Euro Truck Simulator 2

The "patched" status of many of these extreme speed mods often refers to major updates, most notably the transition to version 1.37 and beyond. Developers introduced several changes that rendered older speed hacks obsolete:

To push a truck toward the 400 km/h mark in current versions of ETS2, you must address three distinct layers of speed limitation: Disable In-Game Limiter: Options > Gameplay menu, uncheck the Truck Speed Limiter

Ensured compatibility with the latest game version.

By default, ETS2 enforces a strict speed limiter to reflect real-world European trucking laws. To exceed this without mods, you can manually disable the "Truck Speed Limiter" in the menu. However, even with this off, standard truck engines and gearboxes aren't designed to reach extreme speeds like 400 km/h. How the 400 km/h Speed Mod Works

To achieve these speeds, players must bypass several vanilla game restrictions: Steam Workshop::Increased Road Speed Limits