Do Mufflers Affect Gas Mileage?

The type of muffler installed on a vehicle does affect its fuel economy. Many aftermarket exhaust systems can manage to produce between 2 and 10 percent gains in fuel economy and power.

Car companies produce exhaust systems for most cars to be restrictive and quiet. Most auto manufacturers aim to build cars for the general public who prefer quiet sounding automobiles. Because of this, many standard mufflers are part of a restrictive exhaust system. Attaching different sized mufflers can increase the flow of the exhaust gases and allow the engine to breathe better.

The three types of performance mufflers available are reactive, absorptive or a combined version of the two.

  • Reactive mufflers
  • Reactive mufflers use engineered plates and perforated tubes to isolate unwanted sounds of an engine. Although these mufflers still manage to keep the vehicle quiet, they also tend to get rid of unwanted back pressure and provide more power and fuel economy.

  • Absorptive mufflers
  • These mufflers are styled straight through. There is packing inside the tubing that helps cancel out noise. Unfortunately, the packing tends to burn out which can create back pressure and impede its performance ability.

  • Combination mufflers
  • These mufflers combine the best of the two and create nice exhaust notes without negatively impacting performance. They provide more power and fuel economy without sacrificing sound.