The 2027 Silverado and Sierra Finally Get a 34-Gallon Tank, Beating Ram and Toyota
The Silverado 34-gallon tank is finally here for 2027, addressing one of the GMC Sierra’s biggest weaknesses, too.
The redesigned 2027 Chevrolet Silverado 1500 and GMC Sierra 1500 will offer an approximately 34-gallon extended-range fuel tank. GM will pair it with the 5.7-liter V8, 6.6-liter V8, and 3.0-liter Duramax diesel. The larger tank gives GM more available fuel capacity than the Ram 1500 and Toyota Tundra. Ford’s F-150 still holds the overall lead with an available 36-gallon tank.
That sounds like a minor specification. For anyone towing a camper or taking a family road trip, however, it could be one of the 2027 trucks’ most useful changes.
The Current Silverado and Sierra Tanks Are Too Small
The current Silverado and Sierra’s fuel capacity has been a genuine weak point, especially while towing.
During a 2,000-mile towing test with a Chevrolet Silverado 1500 Duramax, Pickup Truck + SUV Talk averaged between 13 and 15 MPG while pulling a trailer. The bigger problem was the truck’s 24-gallon tank, which limited towing range to roughly 300 miles and required more fuel stops than expected.
Pickup Truck + SUV Talk encountered the same 24-gallon capacity in a GMC Sierra 1500 AT4 Duramax during a separate towing comparison.
That is the part that matters. A diesel engine can return excellent highway fuel economy, but a relatively small tank limits how far the truck can take advantage of it. The problem becomes more obvious while towing, when fuel economy drops and convenient fuel stops can be harder to find.
The Silverado 34-Gallon Tank Changes the Conversation
GM says the Silverado 34-gallon tank will be available with both sixth-generation Small Block V8 engines. Those include the 402-horsepower 5.7-liter V8 and the 481-horsepower 6.6-liter V8. GM will also offer the extended-range tank with the returning 3.0-liter Duramax diesel.
The 2.7-liter Enhanced TurboMax is not included in GM’s list of engines eligible for the larger tank. That engine makes 350 horsepower and 455 lb-ft of torque for 2027, and every Silverado and Sierra engine will now be paired with a 10-speed automatic transmission.
Chevrolet.com specifically lists the approximately 34-gallon tank among the highlights of the new Silverado ZR2. The ZR2 comes standard with the 3.0-liter Duramax and offers the 6.6-liter V8 as an option.
The larger tank is not limited to the off-road truck, either. Pickup Truck + SUV Talk was able to include the extended-range gasoline tank on an early order for a 2027 Silverado High Country equipped with the 6.6-liter V8.
We have already broken down the 2027 Silverado’s new engine lineup and pricing, along with the engineering behind GM’s sixth-generation Small Block V8s. The larger tank may not produce the same headline numbers as 481 horsepower or 13,700 pounds of maximum towing, but it could make a bigger difference during an actual towing trip.
GM Now Beats Ram and Toyota, but Not Ford
Here is how the largest available fuel tanks compare among the current and upcoming half-ton trucks:
| Truck | Largest available fuel tank |
|---|---|
| Ford F-150 | 36 gallons |
| 2027 Chevrolet Silverado 1500 | “Approximately 34 gallons” |
| 2027 GMC Sierra 1500 | “Approximately 34 gallons” |
| Ram 1500 | 33 gallons |
| Toyota Tundra | 32.2 gallons |
Toyota made its 32.2-gallon tank standard across the entire 2026 Tundra lineup. Ram offers 26- and 33-gallon tanks depending on configuration, while Ford’s F-150 capacities include 23, 30.6, and 36 gallons depending on wheelbase and engine.
GM has confirmed that its 34-gallon tank is available, but it has not published a complete chart showing which Silverado and Sierra configurations receive it as standard equipment.
Still, GM has finally moved beyond Toyota and Ram in terms of maximum available capacity. Ford remains ahead, but only by about 2 gallons.
The Duramax Could Travel More Than 900 Miles
The biggest potential winner is the 3.0-liter Duramax.
GM estimates that a 2WD Duramax will return 27 MPG on the highway. Pair that rating with the available 34-gallon tank, and the math produces a theoretical 918 miles of highway range. GM officially describes it as more than 900 miles between fill-ups.
That figure will naturally depend on configuration and driving conditions. GM’s calculation specifically uses its estimated 27 MPG highway rating for a 2WD Duramax, and the automaker warns that actual range may be lower.
Nobody needs to sit in a truck for 900 consecutive miles to appreciate the added capacity. The benefit is having more control over when and where you stop, particularly while towing or traveling through areas where diesel stations are spread farther apart.
GM Still Owes Us the Complete Fuel-Tank Chart
Several important questions remain unanswered.
GM has not published the standard tank capacity for trucks that do not receive the extended-range tank. It also has not released a complete cab-by-cab, bed-by-bed, and trim-by-trim breakdown showing exactly where the 34-gallon tank will be standard, optional, or unavailable.
Chevrolet’s public page confirms the tank on the ZR2, and an actual High Country order confirms that the extended-range gasoline tank is available outside that trim. However, GMC’s current 2027 Sierra 1500 preview does not provide fuel-capacity details.
We also do not know how much the larger tank will cost when it is optional. Chevrolet has published 2027 Silverado starting prices, but complete option pricing and configuration-specific fuel capacities have not been released publicly.
For more on the redesigned trucks, read our 2027 Chevrolet Silverado 1500 first look and 2027 GMC Sierra 1500 first look.
The Bottom Line
This change was overdue.
The current Silverado and Sierra can tow serious weight, but a 24-gallon tank forces more frequent stops when fuel economy falls under load. Pickup Truck + SUV Talk’s 2,000-mile Silverado Duramax towing test documented exactly that problem.
With the Silverado 34-gallon tank, the 2027 Silverado and Sierra finally move ahead of Ram and Toyota in maximum fuel capacity. Ford still offers 2 additional gallons in the F-150, but GM is close enough that fuel capacity is no longer an obvious weak spot.
Now we just need GM to tell us which buyers can get it, what it costs, and how widely the 34-gallon tank will be offered across the Silverado and Sierra lineups.