The 100 Least Fuel-Efficient Cars in 2004
Have you ever wondered what the least fuel efficient cars manufactured in 2004 are? In this article, we'll list out the worst 100 cars from 2004 for fuel efficiency with information on each of them!
How to Determine Fuel Efficiency
The list of the best fuel efficient cars on this page is based on one simple metric provided to us by the U.S. Department of Energy: the combined miles per gallon (MPG).
This metric is calculated by taking the total miles driven by the car and dividing it by the total gallons of fuel used.
Manufacturers provide this information to the Department of Energy, they provide it to us, and we provide it to you after sifting and organizing it.
The combined miles per gallon (MPG) is a measure of how much fuel the car uses per mile and is a good indicator of how efficient the car is. It's a combination of both city and highway driving, to give you a more overall accurate MPG.
With that out of the way, let's dive into the list. You can click the links in the table below to see more detailed information about each car.
Worst 2004 Cars by Miles per Gallon
Conclusion
The least fuel efficient car of 2004 is the Chevrolet Silverado 2500 HD 2WD CNG. It has a combined MPG of 10 and costs $3,500 per year to drive it.
Least Fuel Efficient Cars By Year
Link To or Reference This Page
If you use this page in your research, please reference MPG Buddy as the source.
<a href="https://mpgbuddy.com/least-fuel-efficient-cars-in-2004">The 100 Least Fuel-Efficient Cars in 2004</a>
"The 100 Least Fuel-Efficient Cars in 2004." MPG Buddy. Accessed on January 3, 2026. https://mpgbuddy.com/least-fuel-efficient-cars-in-2004.
"The 100 Least Fuel-Efficient Cars in 2004." MPG Buddy, https://mpgbuddy.com/least-fuel-efficient-cars-in-2004. Accessed January 3, 2026.
The 100 Least Fuel-Efficient Cars in 2004. MPG Buddy. Retrieved from https://mpgbuddy.com/least-fuel-efficient-cars-in-2004.