Is your 2015–2016 GM 6.6L Duramax LML still depending on the factory fuel system when your build demands more? The PureFlow AirDog II-5G adds a dedicated lift pump to the LML and improves the quality and consistency of the fuel reaching the injection system. These trucks don't come with a factory lift pump, making the AirDog a worthwhile upgrade for maintaining steady fuel delivery and supporting additional fueling. Choose from 100 GPH, 165 GPH, or 220 GPH, depending on your truck's configuration.
The 100 GPH and 165 GPH systems mount on the frame ahead of the fuel tank, draw fuel through the factory fuel module's suction fitting, and feed the factory injection pump line directly. Air and vapor separated by the AirDog are returned to the tank through a filler-neck tee, creating a more consistent supply to the engine. For serious builds, the 220 GPH uses a cradle bracket on the factory frame standoff, a 5/8-inch draw straw in the tank, and connects to the factory 1/2-inch fuel line; its return is routed through the modified factory 12mm suction line. All three systems are manufactured in the USA and are designed specifically for 2015–2016 LML Duramax trucks.
Which Flow Rate should you choose?
When it comes to upgrading your fuel system, choosing the right GPH (gallons per hour) rating isn’t about picking the biggest number; it’s about matching your pump to your truck’s real-world demands. An AirDog aftermarket fuel system doesn’t just supply fuel; it improves filtration, removes air/vapor, and ensures your injection system gets consistent, reliable pressure. But choosing between 100, 165, and 220 GPH? That’s where a lot of people get stuck.
100 GPH: Stock Reliability Upgrade (STOCK-500 HP)
- Perfect for stock trucks or very mild setups. If you want to eliminate factory fuel issues and improve reliability without overbuilding your system, this is the ideal choice.
165 GPH: Daily Driver + Towing Sweet Spot (500-800 HP)
- Best for trucks with mild tuning or regular towing. This is the most popular option for owners who want extra fuel capacity without going overkill.
220 GPH: Performance Builds (1000+ HP)
- Designed for higher horsepower setups with increased fuel demand. Ideal for trucks running upgraded injectors or pushing harder under load.