• Increase Your Diesel Engine’s Fuel Economy & Mileage

       With diesel fuel prices at record highs, it is having a dramatic effect on everyone that drives a diesel-powered commercial truck. Owners of these trucks are looking for any way to save money, and as a repair shop you can help your clients. This blog post will list out areas of the truck you can inspect and recommend to your clients.

       We recommend picking the ones that make sense to your business and technician skill set and then putting a package together. We’d also recommend several marketing strategies to increase sales and opportunities.

    • Charge for the inspection but make it free if you find something wrong.
    • Make the inspection package free and use it as upsell opportunities.
    • Make sure customers know about the promotion. Flyers you hand to each customer that comes into your shop, banners on the outside of your building, email campaigns, and signage at the service write-up desk are all great techniques.
    • Make sure to call it something that is easily understandable, such as “Fuel Economy Efficiency Package”.

       Below is our list of ideas, and feel free to leave comments or reach out to us for additional ideas we should include!

    Tire Pressure

       For every 4 pounds a tire is low, rolling resistance of the tire increases by 5%. This includes both the truck and the trailer. Often customers do not have tire pressure monitoring systems or neglect to check their tire pressure regularly.

    Air Filters

       Dirty air filters cause the intake to become restricted, which means your engine works harder, which means it uses more fuel.

    Charge Air Cooler

       When I was a service manager, we purchased a charge air cooler test kit and tested every single truck that came into the shop that was more than 3 years old. We sold dozens of charge air coolers each month, and it only took us minutes to check. The charge air cooler, hoses, and clamps should all be thoroughly inspected and tested. These are slightly larger repairs but can have a dramatic effect on the customers fuel economy. They cost around $255 on Amazon.


       While most customers do change their engine oil when required, the other systems are often neglected. The main components to inspect are transmission and differential. You can look up maintenance schedules on Diesel Repair for free. For example, certain Allison transmissions needs their oil changed every 25,000 miles!

    Clutch Adjustment

       For customers still running a manual transmission, clutches often need adjustment. When out of adjustment this means the clutch is slipping, which causes poor fuel economy.

    Suspension Components

       A quick visual inspection by a trained diesel technician can easily spot worn out suspension components. Shock absorbers, bushings, loose/stretched U-bolts, and misalignment of components creates drivetrain drag, which creates higher resistance, which decreases fuel economy.

    Check the Engine Computers

       Even if the there isn’t an active check engine light, look at the historic fault codes. If you see recent and/or high counts of codes for turbo overspeed (oil loss), frequent DPF regens, and other fault codes can be indicators or components not operating properly.

       You also want to down a report that shows how the vehicle is being operated. What percentage of time is the truck in idle? How often is the driver in the top 2 gears? By looking at the data from the driving habits you can find opportunities to adjust driver behavior that is causing lower fuel economy.

       At Diesel Laptops we have tools that range from free to over $10,000 that can perform reports, diagnostics, and view this information. Make sure to give the customer a copy of their fault codes and driving habits as well.


    DPF Cleaning

       Almost all commercial trucks since 2007 have a diesel particulate filter, and all of these have required maintenance intervals to remove the DPF and have it cleaned on a machine. Dirty diesel particulate filters will cause restrictions in the exhaust system, which impacts your engines performance and fuel economy. You can look up maintenance schedules on Diesel Repair for free.


       When it comes to fuel economy, it comes down to making small improvements on the vehicle and driving habits. If a truck is getting 7 MPG and drives 100,000 miles per year, that is 14,286 gallon of diesel fuel which costs $79,130 per year at today’s prices. If we can make the vehicle just 1% more fuel efficient, this is the equivalent of saving 141.2 gallons of diesel fuel, or $785.

       Charging a customer for an inspection and testing service $99 or $199 to potentially save them $785 per year for each 1% improvement is a strong return on investment that most customers won’t pass up.

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