Ground vehicles are found in the eighth level "Power Plant". There are two available vehicles in the level, the forklift and the dump truck. For this achievement I would recommend using the dump truck, it's faster. For full speed on the dump truck make sure to hit the drive lever twice to switch it into the fastest gear, then follow the road which loops around the mountain and continue the loop until the achievement unlocks.
Quick route to dump truck: Swing climb the wall opposite the fan at the start of the level then drop down into the area with the three black furnaces and the dump truck.