What is the miles per gallon for an eighteen wheeler?

The miles per gallon (MPG) for an eighteen wheeler can vary significantly depending on several factors such as the specific make and model of the truck, engine type, load weight, and driving conditions. Generally, the MPG for an eighteen wheeler ranges between 5 to 8 miles per gallon on average. However, some newer and more efficient models can achieve MPG ratings of up to 10-12 MPG under optimal conditions. It's important to note that these figures can be affected by factors like idling, traffic congestion, and mountainous terrain.