Pay attention to fuel level. The information is displayed on:
- a dashboard (use [I] to switch between screens) in vehicle interior,
- Route Advisor panel in the lower right corner,
- the main control panel ([Escape]) on the right in "my truck" section.
Additionally, the panel and the dashboard displays information about the range.
When the fuel level is low an appropriate alert will be displayed. However, you should not be so reckless. Sometimes it is very hard to find any gas station. Plan your route carefully including gas stations and do not risk an empty fuel tank.
On a highway a special sign will inform you about approaching a gas station and a park space. In case of ordinary roads, such sign is located close to the station. It is hard to miss it, as usually it is near the road. Use a map to find a station.
To take fuel park near the fuel dispenser where the green icon is displayed. Then turn off the engine ([E] by default) and press the button ([Enter] by default) to take the fuel. It will take a while as the fuel tanks are large, but you have to hold the button the whole time. When the tanks are full the operation is complete. Of course you do not have to tank so much fuel.