How to Improve Fuel Mileage on a Dodge Diesel

The Cummins diesel motor that is supplied in the Dodge Ram is renowned the world over for its power, efficiency and torque. The Cummins also has plenty of possibilities for upgrades to help in other areas besides power, such as air flow, temperature, exhaust temperatures and turbo upgrades. Diesel engines do not use spark plugs like gas engines do, so tune-ups are performed differently on a diesel engine. Routine maintenance can also help with fuel economy, and on a diesel it includes checking the fuel filter, oil filter and tire pressure to ensure optimal performance from your Dodge.

Things You'll Need

  • Air intake system
  • High flow exhaust
  • Ratchet
  • Sockets
  • Phillips head screwdriver
  • Flat head screwdriver
  • Add an air intake system to your Dodge Ram. By increasing the airflow, your Cummins will have a better air-to-fuel ratio, which will increase the efficiency of the motor. Increased efficiency translates to better gas mileage. K & N Filters claims that their intake systems can add as much as 12 horsepower and 2 miles per gallon to a Dodge Ram. Different systems require different tools, and steps involve removing the old air intake and using a Phillips head screwdriver with the supplied clamps to bolt on the new setup.

  • Change the exhaust system on the truck to a more free-flowing unit that will allow the increased air flow to leave the truck just as efficiently as it entered. Aftermarket companies like Silverline, Borla, and Banks Engineering all create bolt-on kits that can be installed in a short amount of time and can help add miles per gallon, as well as power. Banks Power conducted tests with the Dodge Ram 2500 and installed one of their aftermarket exhausts on the test truck. They found a 88% increase in airflow over stock and lower exhaust temperatures also. They also found a 1 to 2 mile per gallon increase in fuel economy with the aftermarket exhaust.

  • Purchase a fuel chip for the truck. These chips reprogram the factory computer and gives the truck new perimeters to operate by. These chips can range in price from $250 all the way to over $1,000 for some of the top-of-the-line units. Installation is usually as simple as plugging in the unit under the dash and following the instructions for the unit. Edge Products produces a chip called Mileage Max that is capable of increasing the Cummins fuel economy by 7% and a power increase of 35 horsepower, all for around $300.

  • Make the upgrades according to your budget. Most people start by increasing the fuel and air efficiency of the vehicle by installing air intake and exhaust systems. These parts tend to be less expensive than alternative upgrades and do provide gains in horsepower and fuel economy. These upgrades alone can combine for 3 to 4 miles per gallon gain as well as an extra 20 to 50 horsepower. This means an extra 120 miles to drive with the standard 31 gallon fuel tank.