January 23, 2020

How to Increase Fuel Mileage on a Diesel Pickup

Written By: ProSource Diesel

Five Simple Steps to Improve Diesel Fuel Economy

With the increasing price of diesel fuel, getting better mileage out of your diesel pickup truck is becoming more important than ever. ProSource Diesel is here to help. The following tips apply to all diesel pickup trucks including the Ford Powerstroke, Dodge Ram Cummins and Chevy / GMC Duramax. These are basic steps that you can accomplish with little effort or money.


If you’re not already maintaining your engine with regular oil changes, tune-ups and filter changes, then those are our first (and most important) recommendations. If you want the most efficiency out of your diesel pickup, you’ll want to make sure all systems are working up to their highest performance level.

We cannot stress enough how important it is to simply replace your fuel filters and air filters. If either or both of those filters are old, your horsepower and fuel economy will suffer. With old or dirty filters, you’ll be trying to get top performance from your engine but making it work harder to accomplish the same task.

A dirty air filter can decrease 20 to 50 horsepower from your performance. It’s like running a mile while wearing old, worn-out shoes. You may finish the mile, but you’ll use a lot more energy doing it, and risk doing damage in the process.

In the same regard, if you haven’t changed your oil in a while, you’re causing extra drag by losing the effectiveness of fresh lubrication. You’re simply not getting the performance you would if your truck had new, clean oil. This extra drag robs you of power.

You’ll also have the same result if you need new transmission oil, transfer case oil and differential oil. If your gears are spinning through thick sludge, they are working much harder than they should, using a lot more horsepower and lowering overall efficiency.

To conclude, get on a regular maintenance schedule for your diesel truck that includes regularly changing your fluids and filters and following the service tasks recommended by your vehicle’s manufacturer.

Synthetic Lubricants

You may be skeptical of the claims by the manufacturers that using their synthetic lubricants will increase fuel economy. We’re here to tell you that they do in fact help your truck get better gas mileage. Replacing regular motor oil with synthetic oil has been shown to increase fuel economy by between 2% and 5%. You may be thinking that’s not a whole lot, but synthetic lubricants are not just for your engine. You can also use them in your transmission, transfer case and both the front and rear differential.

Synthetics simply do a better job at lubricating moving parts and reducing friction. Friction reduction equals easier moving diesel parts which in turn equals better fuel mileage. If you reduce friction, both horsepower and fuel economy will go up.

Monitor Your Boost

You could file this in the maintenance section, but this topic is so important it needs to be discussed all on its own. You may think you don’t need a boost gauge and that it doesn’t serve a purpose, it’s just there because it’s fun to watch. While it is fun to watch, it definitely does have a purpose.

Boost is directly related to your turbocharged diesel engine’s performance. It shows how much power your truck is making. To put it simply, more boost equals more power. So why do we have to keep an eye on our boost gauge? Let’s say you know your truck’s power level is supposed to have 20psi of boost.

If you’re aware of that and suddenly see a decrease, you can catch small problems that might otherwise go unnoticed. These small problems in the system could be the reason for the decreasing power output and could indicate other issues that affect both power and fuel mileage. So, by monitoring boost, you can be aware when there’s something out of sync.

While others may drive around complaining about how they’re having to fill up their tank more often than before, you will be aware that something needs to be looked into, either by yourself or a qualified mechanic. It could be a loose clamp, a problem with your intercooler boot, a slight leak in the exhaust pipe of the turbocharger or a dirty air or fuel filter. Regardless of what the issue is, you’ll know that something’s not quite right thanks to keeping an eye on your boost gauge.

Reduce Your RPM

If you’re new to the diesel world you may want to drive your diesel truck like you did your regular gas-powered truck. That’s fine, you won’t hurt your engine, but you will hurt your fuel economy. To get the best mileage out of a diesel engine, you need to increase to the speed limit gradually, not punching the accelerator as soon as the light turns green. Diesel trucks don’t like to be rushed into action.

Although newer trucks have increased horsepower in the higher RPMs, low-end torque is where you want to be for better fuel economy. Use the minimum amount of throttle to get up to the speed you want. Once you get your truck into overdrive, let the torque move the load down the road and you’ll improve your mileage.

Improve Air Circulation

To make your engine run more efficiently, you need to get more air in and get more air out. We recommend working on the fresh air intake side and the exhaust side to get a boost in mileage. This one may set you back a few dollars, but the improvement will be well worth it.

A performance exhaust system can do a world of good for improving the mileage in your diesel truck. If you can afford it, installing a 4-inch free-flowing exhaust and cold air intake are your best options.

Looking at the intake side, simply adding a BD Diesel high flow air filter will help tremendously. This type of air filter allows more airflow and in turn, lowers exhaust temperatures while increasing horsepower. On the exhaust side, a Spoologic performance turbocharger is the best way to get the air out. It can provide up to 33% more airflow.

We hope this information has helped you better understand how your diesel truck works and how to get the best fuel mileage out of it. If you have any questions about diesel truck parts please send us an email or give us a call. We’ll be happy to help.

See you on the road!


  1. SEO Service on January 31, 2020 at 1:12 PM

    Awesome post! Keep up the great work! 🙂

  2. AffiliateLabz on February 15, 2020 at 9:07 AM

    Great content! Super high-quality! Keep it up! 🙂

  3. Dean on March 25, 2020 at 9:12 AM

    I just want to say Thank You for your help.

    You guys delivered the parts I needed while Ford Dealer couldn’t even find them for me.

    Keep up great job.

    Hope to share pics and stories soon.

    Dean W. Minnesota

  4. Chad Biddle on May 1, 2020 at 3:16 PM

    I have a 1998.5 dodge 2500. Im getting twenty two miles to gallon. The only thing i havent got on my truck is the cold air intake but i keep the air filter clean. And keep up with oil and fuel filters. I run lucus oil treatment. In my truck with the synthetic. 248000 miles on it. So i think im doing ok

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