Fuel-Saving Tips for Used Trucks

Diesel prices can fluctuate by the week, but one thing stays constant: operating an older truck eats into profits if it’s not optimized for fuel efficiency.

For Canadian owner-operators running used trucks, smart fuel-saving strategies are not a luxury — they’re essential. Between routine wear-and-tear and outdated tech, older rigs are naturally less efficient than their newer counterparts. But that doesn’t mean you’re stuck with poor mileage.

In this guide, we’ll break down proven strategies to reduce fuel consumption in older diesel trucks, from basic tire checks to aerodynamic upgrades — all designed to improve performance without breaking the bank.

Why Older Trucks Consume More Fuel

Used trucks, especially those with over 500,000 km, face several fuel efficiency hurdles:

• Engine Wear: Pistons, injectors, and sensors degrade over time, making combustion less efficient.
• Outdated Technology: Older models lack modern fuel management systems and aerodynamic designs.
• Mechanical Drag: Aging wheel bearings, misaligned axles, and sticky brakes increase rolling resistance.
• Driver Fatigue: Without modern cruise control or torque assist, drivers may accelerate inefficiently.

These challenges don’t mean older trucks can’t be competitive — they just require intentional maintenance and strategy.

Best Practices to Cut Fuel Costs in Used Trucks

Let’s look at practical, cost-effective ways to reduce diesel consumption without buying a new unit.

Maintain Optimal Tire Pressure

Underinflated tires can reduce fuel economy by up to 2%. That’s thousands in wasted fuel over the year for long-haul drivers.

Fuel-saving tip:

• Check pressure weekly with a calibrated gauge
• Match inflation to load weight and temperature fluctuations
• Rotate tires regularly to maintain even tread wear

Check eligible tire financing options if you’re considering replacements.

Align the Axles

Even minor axle misalignment can create drag, especially at highway speeds.

What to do:

• Schedule axle alignment at least twice a year
• Pay attention to uneven tire wear — it’s a telltale sign of misalignment
• Use a certified heavy-duty truck shop to ensure proper geometry

This not only improves mileage but extends suspension and tire life.

Upgrade Aerodynamics

Older trucks lack many factory-installed aerodynamic features found in today’s models. But you can retrofit yours to minimize wind resistance:

• Install side fairings and roof deflectors
• Use aerodynamic mud flaps and wheel covers
• Lower your trailer gap (ideal: less than 36 inches)

These changes can improve highway fuel efficiency by 5–10%.

Explore trailer financing options if you're upgrading your entire unit.

Reduce Idle Time

Idling for just one hour per day can cost over $2,500 in fuel annually. Older engines, in particular, suffer from inefficient idling due to looser tolerances and poor thermal control.

Tips:

• Use automatic engine shut-off timers
• Consider auxiliary power units (APUs) for climate control during rest breaks
• Train drivers on fuel-conscious habits

If you’re financing a used truck, explore working capital loans to help afford APU installations.

Stay on Top of Preventive Maintenance

Regular service has a direct impact on fuel economy, especially for trucks with aging fuel systems or turbochargers.

Key checks include:

• Fuel filter replacements every 15,000–30,000 km
• Turbocharger inspections for boost leaks
• Injector timing and spray pattern analysis

Review our truck repair financing options if you're facing expensive service costs.

Use Synthetic Lubricants

Synthetic oil reduces engine friction and flows more efficiently in cold climates — especially relevant across Canadian routes.

Benefits:

• Reduces fuel consumption by 1–2%
• Extends oil change intervals
• Protects older engines better under stress

Switching to synthetic lubricants can save hundreds per truck per year.

Shift Smarter

Old habits can burn diesel fast. Use progressive shifting — moving up gears just before peak torque — to minimize fuel-wasting revs.

Train for efficiency:

• Upshift at lower RPMs (~1,300–1,500 RPM)
• Downshift gradually using engine braking
• Avoid sudden throttle bursts during overtakes

Monitor Speed

Every 10 km/h over 90 km/h can reduce fuel economy by up to 10%. Cruise control is a useful tool, but manual adjustments often do better on hilly terrain.

Install Fuel Monitoring Tech

Telematics and fuel tracking systems are not just for fleet managers. Many are affordable and integrate with older trucks.

Features include:

• Real-time fuel tracking
• Idle time alerts
• Route optimization tools

Consider a business line of credit to cover recurring tech upgrades.

Consider a Professional Tune-Up

A full ECM tune or recalibration can optimize an older truck’s performance and economy — particularly after an engine rebuild or transmission retrofit.

While this can cost upwards of $1,000, the ROI in fuel savings is usually under 12 months.

Case Study: Fuel Optimization in a 2015 Freightliner

A long-haul operator recently came to us after purchasing a used 2015 Freightliner Cascadia. While the truck was in excellent cosmetic condition, his fuel bills were climbing rapidly — averaging over 40 litres per 100km.

After a consult, he:

• Aligned his axles and installed new drive tires
• Upgraded to synthetic engine and transmission oils
• Replaced the fuel filter and EGR sensor
• Installed a roof fairing and wheel covers

With the help of an equipment loan, the upgrades were completed in under two weeks. Within the first 30 days, his fuel efficiency improved by 11%, saving him over $900.

Frequently Asked Questions

How much can I realistically save on fuel by upgrading an older truck?
Most owner-operators see 5–15% savings with consistent maintenance and aerodynamic upgrades — equal to thousands per year.

Are there financing options for used truck upgrades?
Yes. Equipment loans, repair financing, and working capital loans can help cover parts and labor.

Is it worth installing aerodynamic kits on older trucks?
Absolutely. Side skirts, fairings, and deflectors can improve highway fuel economy by 5–10%, with payback periods under 6 months in most cases.

How does driver behavior affect fuel economy?
Driver habits like excessive idling, speeding, and improper shifting can reduce fuel efficiency by up to 30%. Training and tracking tools help address this.

Can I finance new tires to improve fuel economy?
Yes. Tires are eligible equipment under most of our financing programs.

Where can I estimate my monthly payments for upgrades?
Use our loan calculator to project costs based on term, interest rate, and loan size.

Fuel savings don’t require a brand-new rig. With smart upgrades, disciplined habits, and the right financing structure, even a 10-year-old truck can run lean and cost-effective.

If reducing operating costs is a priority this quarter, our credit analysts are available to walk you through financing options that fit your budget and business model. Whether you're planning an overhaul or looking to spread the cost of new parts, we're here to help make the numbers work.

Connect with a financing expert and start putting your fuel savings strategy into motion today.

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