2027 Sierra 1500 Duramax Gets a 34-Gallon Fuel Tank

One of the biggest updates for the 2027 GMC Sierra 1500 Duramax isn't under the hood. It's the fuel tank.

GMC has confirmed that an approximately 34-gallon fuel tank will be available with the 3.0L Duramax Turbo-Diesel. When equipped with the larger tank, GMC estimates the Sierra 1500 Duramax can deliver more than 900 miles of highway driving range.

That's a major upgrade for long-distance driving and towing, giving Duramax owners considerably more range between fuel stops.

Fuel tank capacity will depend on cab configuration:

  • Regular Cab: Available 28-gallon tank

  • Double Cab: Available 34-gallon tank

  • Crew Cab: Available 34-gallon tank

The 3.0L Duramax itself continues to produce 305 horsepower and 495 lb-ft of torque, but the larger available fuel tank makes the diesel an even more attractive option for buyers focused on range and efficiency.

Which 2027 Sierra 1500 Trims Get the 3.0L Duramax?

GMC is keeping the Duramax available across a large portion of the redesigned Sierra 1500 lineup.

2027 Sierra 1500 Duramax availability:

  • Pro: Available

  • Elevation: Available

  • AT4: Available

  • AT4X: Standard

  • Denali: Available

  • Denali Ultimate: Available

The biggest change is the AT4X, which now comes standard with the 3.0L Duramax and the approximately 34-gallon fuel tank.

That gives the most off-road-focused Sierra an interesting combination right out of the box: 495 lb-ft of diesel torque, more than 900 miles of available GM-estimated highway range, 35-inch mud-terrain tires, front and rear electronic locking differentials, and a 2-inch factory lift.

For buyers who want the redesigned 2027 Sierra but still prefer the efficiency and torque of the Duramax, GMC isn't limiting the diesel to a handful of configurations. It's available from the work-focused Pro all the way through Denali Ultimate, while becoming standard equipment on the AT4X.