Most folks buy a Cummins-powered truck because they want strength, towing capacity, and reliability. Fuel mileage usually isn’t the first thing on their mind. But after a few years of paying for diesel, that question comes up a lot: “Can I make this thing more fuel efficient without losing power?” The short answer: yes, with the right upgrades. We’ve seen it happen plenty of times at Brandell Diesel.

Why Cummins Trucks Don’t Always Sip Fuel

Heavy-duty trucks aren’t small cars. They’re pulling trailers, idling on job sites, and running long miles with heavy loads. All of that drags MPG down. Add in dirty filters, worn injectors, or old tuning, and it gets worse. A lot of drivers also think “more horsepower means worse mileage,” but that’s not always true. With a Cummins, efficiency really comes from how cleanly and effectively it burns fuel.

Upgrades That Actually Help

Custom Tuning

We had a customer with a 3500 that did a lot of highway towing. Stock tune had him running rich and wasting fuel. After a re-map, he picked up about 2 MPG while towing the same load. Tuning makes a big difference when it’s matched to how you actually drive.

Airflow (Intake & Filters)

Think of it like breathing through a straw vs. breathing normally. A restrictive intake chokes the motor. A cold air intake or high-flow filter gives it room to breathe, which makes combustion cleaner and mileage better.

Exhaust Work

If air gets in easier, it also needs to get out easier. A less restrictive exhaust reduces backpressure. We usually recommend pairing intake and exhaust upgrades for the best result.

Turbo & Injectors

An efficient turbo spools faster, so the engine isn’t working as hard. And injectors? If they’re worn or dirty, they’re literally dumping fuel out the tailpipe. We’ve seen trucks gain both power and economy just by refreshing injectors.

Don’t Forget the Basics

You don’t always need fancy parts. Tire size, gearing, and even driving style play a big role. Put oversized tires on without adjusting gears and you’ll kill mileage fast. Carrying around unnecessary weight does the same. And yes — gentle throttle and steady cruising save fuel, even on a Cummins.

Why Trust Brandell Diesel

There’s no one-size-fits-all recipe. What works for a ranch truck that tows cattle trailers isn’t the same as a daily driver running mostly highway miles. At Brandell Diesel, we look at how you use the truck first. Then we suggest upgrades that balance power with efficiency. We only use quality parts and back our installs with diagnostics and support, so you know the gains are real — not just on paper.

Final Word

With the right Cummins engine upgrades, you don’t have to choose between power and fuel economy. You can have both. The trick is picking upgrades that match your truck and your lifestyle. If you’re tired of watching fuel costs climb and want to make your Cummins a little more efficient, bring it by Brandell Diesel. We’ll walk you through options, explain what’s worth doing, and help you get more miles out of every gallon.

How Upgrades Can Make Your Cummins-Powered Truck a Fuel-Efficient Beast