Gas Station Simulator

You get this achievement for putting fuel into ten different cars in the game.

As long as you have gotten through enough of the game to sell fuel (following the prompts the game gives you to move it along) and you have the station open, cars will come and want to get fueled up. The game will inform you that you have waiting customers for fuel. RT on the fuel dispenser and then RT on the fuel tank of a waiting car to fill it up. Do this ten times and the achievement will pop.