With the overwhelming popularity of the dual mode exhaust systems on the 2015-2016 Dodge Challenger SRT Hellcat and the Dodge Charger R/T Scat Pack, Dodge made the decision to offer a loud dual mode exhaust system standard on 2017 (and later) Dodge Chargers and Challengers equipped with a Hemi V8 engine.
When those 2017 models were introduced in the Hellcat and Scat Pack trimlines, they came loaded with a 2.75-inch dual mode exhaust system that let the Hemi engines howl when pushed, while still quieting down in more gentle driving situations. The advantage to this system is that it allows drivers to let that high-performance engine scream when it is opened up, but still not bother the neighbors when you are warming the car up before going to work.
Second only to horsepower, the sound of these dual mode exhaust system on the 2015-2016 Dodge Challenger and Charger Scat Pack and Hellcat were a favorites feature for owners. This, however, left owners of the models sporting the 5.7L Hemi V8 engine to look for aftermarket exhaust components to get a similar sound. In 2017, that changed. That's when every Dodge Challenger and Charger with a Hemi engine came equipped with the 2.75-inch dual mode exhaust system.
Dual Mode Exhaust for All Hemi Muscle Cars
This means, starting with the 2017 model year, the Challenger in R/T, R/T Plus, R/T Shaker and R/T Shaker Plus trimlines and the Charger in R/T and R/T Road & Track trimlines are equipped with the same growling exhaust system as the Scat Pack and Hellcat models.
How the Dual Mode Exhaust System Works
The dual mode exhaust system in each Hemi-equipped Dodge Challenger and Charger employs a pair of electronic valves situated toward the rear of the vehicle. These valves are in place to control the output of the exhaust noise. These valves are closed to keep sound levels at a minimum when the engine is idling and/or in light throttle situations. The setting also assists in minimizing the "drone" sound during highway driving. When you put the pedal to the metal, though, those valves open up and the exhaust starts to roar.
This exhaust system is covered by Mopar's Maximum Care plan.