Is It Worth Upgrading Your Rig for Better MPG?
September 25th, 2025
By Arrow Truck Marketing
With diesel prices rising and sustainability becoming a top priority, many owner-operators and fleet owners are asking: Is it time to upgrade to a more fuel-efficient semi-truck? It’s a smart question, with far more factors than just sticker price.
Why Fuel Efficiency Matters More Than Ever
Fuel is one of your largest operating costs. Even slight improvements in fuel economy translate to real monthly savings. Plus, newer trucks mean fewer idling hours, cleaner emissions, and an easier time meeting evolving truck efficiency and emission standards. Before jumping into a purchase, let’s break down whether you’ll get your investment back through fuel savings, downtime reduction, and resale value.
What Impacts MPG?
Many elements influence your rig’s fuel economy:
Aerodynamics plays a role in improving MPG
. SmartWay verified features such as sleek fairings, gap reducers, tractor-trailer skirts, and boat tails can reduce drag and improve fuel economy. According to the EPA, many combinations of aerodynamic enhancements can boost fuel economy up to 9%, saving thousands of dollars and reducing tons of CO₂ emissions per year.
New, lightweight, aerodynamic trailers can push
to over 20%.
Trailer aerodynamic devices alone, such as side skirts and tails, typically deliver savings of 5% to 9%.
Even
tires can affect fuel efficiency
. Low rolling-resistance tires and properly inflated super-single tires yield
over time.
Engines that meet modern EPA standards, especially post-2017, typically reduce fuel use by up to 20%. If you have a truck older than 2017, that means you have lots of room to improve.
Fuel-management systems that monitor consumption and support real-time decisions give drivers real insights into habits that affect fuel economy.
Across entire fleets participating in recent studies, the average fuel economy climbed to 7.77 MPG in 2023, up from 7.62 MPG in 2022 and 6.67 MPG ten years ago, a meaningful improvement that’s tied directly to the adoption of efficiency technologies such as those listed above.
Incremental Upgrades vs. Full Truck Upgrade
What do all of these statistics mean?
Optimize what you've got first. Boosts in efficiency often come from habits and maintenance:
Minimize idle time
Use progressive shifting
Monitor tire pressure
Keep up with air filter and oil changes
Train drivers for smooth acceleration
These changes are low-cost – or even no-cost – and are often overlooked.
Aftermarket aero add-ons like skirts, tails, wheels, and fairings carry moderate up-front costs (often $1,000–$3,000) and pay back through fuel savings in less than two years, according to SmartWay and other data.
ROI: Fix vs. Replace
When you compare upgrading vs. retrofitting, here’s a snapshot:
Option | Upfront Cost | Fuel MPG Gain | Estimated ROI |
Aero Add-ons | $1,500–$3,000 | 5–10% improvement | Payback in 12–24 months |
New Fuel-Efficient Truck | High | 10–20% improvement | Depending on miles driven and cost, still profitable long-term |
Aero upgrades offer a relatively quick payback, typically in 12 to 24 months, based on average fuel savings. Retrofitting with devices like side skirts or trailer tails provides consistent MPG gains without the financial commitment of a new truck.
In contrast, a full truck upgrade delivers even more significant improvements in fuel economy, especially when the new rig is equipped with advanced aerodynamics and an EPA-compliant engine. However, the higher upfront cost means you’ll want to run the numbers carefully to determine when that investment makes sense.
The table above helps clarify the decision: if the fuel savings from a newer truck exceed your loan payments and operating cost reductions, the long-term ROI can be favorable. If not, incremental upgrades may deliver better value, especially when paired with disciplined maintenance and fuel-conscious driving.
Calculating Your Next Move
To evaluate what’s right for your operation:
Track your current MPG and monthly diesel spend.
Estimate yearly miles.
Calculate actual savings from potential MPG gains.
Compare that against the upgrade or retrofit cost.
Factor in resale value, uptime, and maintenance efficiency.
New Technology vs. Used Trucks
New big rigs, like the latest Freightliner Cascadia or EPA-compliant models, offer improved aerodynamics, efficient engines, and tech built in. But used trucks with good specs can still offer a sizable MPG improvement at a lower investment. In markets moving toward sustainability, even a used model with updated aero packages can deliver a strong ROI without the premium of a new one.
Knowing When to Upgrade
Upgrade your rig when:
Your current truck has high mileage and is prone to repairs.
You run high volumes, and the MPG gain covers loan payments plus profits.
Your operations require compliance with newer emission mandates.
You want lauded reliability and peace of mind.
Retrofitting is smart when:
Your rig still holds good market value.
Major maintenance isn’t overdue.
You’re not ready to stretch capital for a new rig.
When MPG Should Lead the Truck-Buying Conversation
Whether you're considering a brand-new truck or buying used, MPG must be in your decision matrix. With escalating fuel costs and tightening regulations, fuel economy can't be an afterthought. A well-equipped used truck often offers excellent value if MPG is a priority.
Arrow’s team understands the critical balance between upfront costs and operating efficiency. We’ll help you assess your truck’s spec, calculate expected MPG, and guide you toward a model, new or used, that aligns with your business goals and budget. Let our expertise help turn MPG into profit.
You don’t have to leap into a new truck immediately to improve fuel efficiency. Start by optimizing driving habits and installing aerodynamic upgrades. If your operation demands more miles and tighter margins, a fuel-efficient upgrade might be your smartest move yet. Either way, focus on smart calculations, not hype, and keep the road ahead profitable.
