24 MPG combined won’t win any hypermiling competitions, but for a full-size, four-wheel-drive pickup truck like the 2021 Ram 1500 with the 3.0L diesel engine, it’s an impressive figure. It’s a good balance between capability and frugality, one that appeals to truck owners who need towing and hauling ability but don’t want to spend too much on fuel during daily driving.

City and highway performance

The EPA estimates 21 MPG in the city and 29 MPG on the highway. The turbodiesel’s torque is important. It allows the Ram 1500 to cruise easily on the highway, which results in better fuel efficiency. Even in city driving, the diesel’s low-end torque means less reliance on heavy throttle, leading to those 21 MPG figures. The eight-speed automatic transmission also plays a key role, keeping the engine at its best RPM for both power and efficiency.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2021 Ram 1500 4WD 3.0L diesel is $2,300. This is based on driving 15,000 miles per year and assumes current national average fuel prices. Your actual fuel costs will vary depending on your driving habits, city versus highway driving, and fuel prices. This $2,300 figure is a benchmark for comparing the Ram’s fuel costs with its competitors, or even with other Ram 1500 configurations. Reviewing 1500 MPG across all years is useful.

Real-world expectations

While the EPA estimates are a baseline, real-world MPG can vary. Towing, hauling heavy loads, aggressive driving, and tire pressure can impact fuel economy. Many owners of the 3.0L diesel Ram 1500 report consistently achieving figures close to the EPA estimates, especially on longer highway trips. Expect slightly lower numbers if you mostly drive around town and frequently use the Ram for heavy-duty tasks, but it should remain competitive compared to other trucks with similar capabilities.

How it compares

The 2021 Ram 1500 3.0L diesel is better than gasoline-powered full-size trucks. For example, the 2021 Ford F-150 with the 3.5L EcoBoost V6 and four-wheel drive achieves around 20 MPG combined. A Chevy Silverado 1500 with the 5.3L V8 is rated at around 17 MPG combined with four-wheel drive. Even the smaller gasoline engines in these trucks struggle to match the diesel’s efficiency. The previous-generation Ram 1500 with the 3.0L diesel had similar numbers. If fuel economy is a priority in a full-size truck, this Ram offers an advantage. You can view all Ram fuel economy data on our site.

Tips to maximize efficiency

It’s tempting to drive the Ram 1500 3.0L diesel hard. The engine works at lower RPMs to deliver peak torque, so maintaining momentum boosts fuel economy. Avoid quick starts and hard acceleration, letting the diesel’s torque do the work. Watch traffic and use cruise control to maintain a steady speed.

Tire pressure is important. Make sure your tires are properly inflated to the recommended pressure listed on the doorjamb sticker. Underinflated tires increase rolling resistance, which reduces fuel economy. Check your tire pressure regularly, especially during temperature changes.

Reduce aerodynamic drag. Use a bed cover or tonneau cover. This helps smooth airflow over the truck bed, which can improve highway fuel economy. Also, remove unnecessary items from the truck bed or roof that could create drag.

Diesel engines work best with regular maintenance. Ensure that all scheduled maintenance, including oil changes and filter replacements, are performed on time. A well-maintained engine will run more efficiently and deliver better fuel economy.