Sound can make a huge difference in the driving experience, both for better and for worse – too much noise can make a longer drive unbearable, while not enough noise can make the driving experience too tame. Luckily, GM offers a dual-mode active exhaust system capable of offering the best of both worlds, depending on the situation at hand. Now, we’re getting an earful of the dual-mode active exhaust on the GMC Sierra AT4 with the following GM Authority exclusive video.
Hosted by GM Authority Executive Editor Alex Luft, the video is four minutes, 45 seconds long and includes some info on the exhaust system, as well as start-up, idle, and revs for the various modes.
As Luft points out, GM first offered the new dual-mode exhaust system (RPO code NPP) for the GMC Sierra 1500 in conjunction with 2024 model year, enabling drivers to adjust the exhaust sound and noise level based on the selectable driving mode. When the truck is in “Normal” mode, the exhaust valves are closed, resulting in a quieter exhaust sound. Switching to “Sport” or “Off-Road” mode opens the exhaust valves, creating a louder, more aggressive exhaust note.
Critically, the NPP dual-mode exhaust is offered exclusively for GMC Sierra 1500 models equipped with the naturally aspirated 6.2L V8 L87 gasoline engine. Check out the table below for more information on the dual-mode exhaust system availability:
| Sport-Mode Enabled Active Dual Exhaust (RPO NPP) | |
|---|---|
| Pro | - |
| SLE | - |
| Elevation | - |
| SLT | A |
| AT4 | A |
| AT4X | A |
| Denali | A |
| Denali Ultimate | S |
In the video, Luft provides a demonstration of the system as equipped by the 2025 GMC Sierra 1500 AT4. Luft captures two cold start demonstrations to showcase the difference in sound between Normal and Sport modes. The first cold start, done in Normal mode, highlights the quiet operation of the closed valves. About 12 hours later, another cold start is performed in Sport mode, showcasing the louder and more aggressive tone when the valves are open.
The difference in sound and noise levels is obvious, and should provide users with an easy way to tailor the driving experience to their liking, whatever the situation may be.
Comments
Very disappointed this feature is not available on the 2025 Yukon Denali. I purposely waited to buy a 2025 to get this feature. Spent $107,000. And still didn’t get everything I wanted.
Give the option on the 5.3 please
I love it!!!
Another dumb decision to limit this. Those girls sijj no t like noise I guess. Or they are rich and just don’t understand why some plebe with a base level truck might want this. The answer is free flow these options. Greed and stupidity overcomes everything
Women may not necessarily like it. Men do.
It depends. A truck which is rugged and growls that is driven BY A SUCCESSFUL MAN, who has worked hard his entire life? Probably yes.
Anyone who buys a truck based on it’s exhaust sound is not dealing with a full deck!
About as dumb of an option as spinners. Why? Just offer the more aggressive “sport” sound and call it a day? Or better yet buyers, save your money on this gimmick option and buy yourself a real exhaust that doesn’t rely on electronics to sound even better than this thing 👍🏼