How to Increase Diesel Fuel Economy

Buying cheap diesel isn't the only way to save money.

Watching for the lowest diesel prices in your area is one way to save on the cost of diesel fuel, but it's not the only way. The way you drive and the way you care for your vehicle can also improve your diesel fuel economy.

Things You'll Need

• Synthetic lubricant
• After-market fuel filter
• After-market diesel exhaust
• Block heater
• Truck tarp

Instructions

1. Do not speed. Not just because it is against the law, but because decreasing your speed just one mile per hour (mph) below 55 mph increases diesel fuel efficiency by 2.2 percent, according to "Overdrive" magazine.

2. Take off some weight. Although it might be a good idea for you to lose a few pounds, in this case your fuel economy will improve with a lighter load in your truck. In stop-and-go traffic and on highways, reducing weight improves your truck's miles per gallon (mpg). Empty your truck bed and remove hitches when not in use. Replacing metal body parts with fiberglass also saves weight.

3. Check the air in your tires. Underinflated tires increase drag, thus reducing your fuel economy. Check the air in your tires regularly to ensure that they are properly inflated.

4. Put a tarp on the load in your truck bed, and your vehicle will become more aerodynamic. According to the Specialty Equipment Market Association (SEMA), drag reduction improves fuel economy by about 6 percent.

5. Lower the road speed limiter on electronically-controlled diesel engines. A lower speed lets you use the top gear, lowering the revolutions per minute (rpm). Disable the fan-on setting with engine break and adjust the engine break so that it does not engage with cruise control. When the truck rolls out after a downgrade, it will go farther, delaying your need to accelerate.

6. Properly shift gears. Shifting gears on a diesel truck at the lowest rpms improves fuel economy, because diesel engines deliver more torque at lower speeds

7. Economize by using a block heater. Instead of idling to raise your engine temperature, use an external heater so you do not waste precious diesel.

8. Replace your conventional motor oil with synthetic lubricants. Synthetic lubes will reduce friction, thereby economizing your diesel fuel use. In a study using Royal Purple synthetic lubricants in a Ford F-250 truck, "Diesel World" improved fuel economy by increasing mileage 10 percent.

9. The most costly of these fixes and one that must be done by a mechanic is to replace your diesel exhaust and air filter system. Larger-diameter after-market exhausts and well-made after-market air filters improve engine efficiency and fuel economy.

References

• "Diesel World" magazine: "14 Ways to Beat High Fuel Prices"
• Synthetic Oil n Lubes: Amsoil Synthetic Lubricants
• "Fleet Equipment" magazine: "Managing $4 Diesel"