2024 Duramax Ram-Air Intake MPG and Sound Test
“I haven’t seen numbers this high in a long time,” says Fix It, Man of his 16.9 mpg 2024 GMC Duramax in bone-stock form. Hoping the Banks Ram-Air Intake would boost both mileage and turbo whistle, he installed it in under 45 minutes, then hit the highway for 200 miles at 78 mph.
Full Video Transcript
00:05 All right, so right now this is with my truck completely stock, and this is about the best fuel mileage I get at 16.9. I actually haven’t seen it this high in a while. So I’ll do a before and after of what it looks like with the new Banks Ram-Air Intake installed. Once I get a few hundred miles on it, I’ll follow up.
00:22 This is with the factory airbox installed. I’m going to do a before-and-after mic’ing up underneath the hood so you can hear what it sounds like. See if there’s any difference in turbo whistle or not.
00:41 Just pulling out at low RPMs. These trucks have been very flat from the factory, so I’m really hoping with the Banks intake to get a little more whistle out of this.
02:01 All right, so we have everything installed now. Relatively easy install—I’d say it took maybe 30 to 45 minutes. I’ll get a video now of what it sounds like installed. [Music]
03:49 I just finished about a 200-mile trip. The majority of that trip, my cruise was set on 78. And you can see I’m now up to 20.5–20.6 miles per gallon, which is much better than what I used to average before on the interstate. It keeps climbing—20.7. I definitely think the Banks intake has made a difference.
04:08 I love the sound of it. It has increased my fuel mileage slightly. Feel like you can’t go wrong here—so check them out. And this is with 35×12.50s on the truck. I’m sure if I still had stock tires on it, it would do even better than this. But yeah—check them out and see what it can do for your truck. [Music]
“I love the sound of it—The intake has increased my fuel mileage. There’s no beating it. So far, I’ve put nearly 1,000 miles on the truck since installing the Ram-Air intake with no issues, no check engine lights.”
What This 2024 Duramax Mileage Test Shows
This owner’s experience provides a useful real-world look at the Banks Ram-Air Intake on a 2024 GMC Duramax. Before the installation, the truck’s dashboard displayed 16.9 mpg. During a later highway drive at approximately 78 mph, the displayed mileage reached 20.5 to 20.7 mpg. The owner also reported more noticeable turbo sound, straightforward installation, and no check-engine light during nearly 1,000 miles of driving.
These readings should be treated as one owner’s observation rather than a guaranteed fuel-economy increase. An accurate before-and-after comparison requires consistent routes, speeds, payloads, weather conditions, tire pressures, fuel-fill methods, and driving habits.
The Banks Ram-Air system is engineered to reduce intake restriction and deliver more air to the L5P Duramax. Banks reports 45% less pressure loss and a 58% mass-airflow improvement over the stock intake. Reduced restriction also allows the turbocharger to produce the same boost while spinning nearly 3,000 rpm slower.
Fitment is model-year specific. The system featured here fits the 2024 6.6L Duramax, while 2025–2026 trucks require a different Banks Ram-Air system.