2026 GMC Sierra 2WD with Sport Mode: MPG and fuel economy

This page collects every fuel-economy figure the EPA publishes for the 2026 GMC Sierra 2WD with Sport Mode. Below you will find the headline combined, city, and highway MPG, the estimated annual fuel cost at three different driving levels, the tailpipe CO₂ emissions, and a full breakdown of the engine and drivetrain. The EPA rates 2 separate variants of this car (different engine, transmission, or drivetrain combinations), and you can compare them side by side in the trims table.

Fuel economy at a glance

These are the EPA's official ratings for the 2026 GMC Sierra 2WD with Sport Mode. The numbers come from a standardised laboratory test cycle and are the same figures that appear on the window sticker of every new car. Real-world mileage varies with driving style, weather, fuel quality, and how heavily loaded the car is.

When the EPA tests several variants of the same nameplate (for example, a front-wheel-drive version and an all-wheel-drive version), each gets its own rating. The figures shown here are the headline variant, taken as the configuration with the best combined MPG. The trims table further down covers all 2 variants side by side.

Combined MPG is a 55/45 weighted blend of the city and highway test cycles. The EPA uses it as the single number you can compare across the entire dataset, including hybrids and EVs (which use the equivalent MPGe figure).

How the 2026 GMC Sierra 2WD with Sport Mode compares

The 2026 GMC Sierra 2WD with Sport Mode returns 19 combined MPG. Cars in the Standard Pickup Trucks 2WD class for the same model year average 24.5 MPG, which puts this car behind the class average by about 22%.

The most efficient car in the Standard Pickup Trucks 2WD class for the 2026 model year is the Tesla Cybertruck Long Range (20in Cyber wheels) at 78 MPG. The bar chart below puts the GMC Sierra 2WD with Sport Mode alongside the class best and the class average so you can see the full picture.

For broader context, the average new car of the 2026 model year (across all classes) returns 45.5 MPG. Larger vehicles pull the all-cars average down, so do not use that figure on its own to judge a small car or a hybrid. The full list of the most efficient cars of the 2026 model year is on its own page.

Trim variants rated for 2026

The EPA rates 2 separate variants of the 2026 GMC Sierra 2WD with Sport Mode. The differences come from the engine size, transmission type, and drivetrain (front-wheel drive, all-wheel drive, and so on). The same nameplate can land several MPG apart depending on the configuration you actually buy.

Annual fuel cost across driving patterns

The headline annual fuel cost the EPA publishes assumes 15,000 miles of driving per year and a fuel mix of 55% city and 45% highway. The dollar figure is calculated using the EPA's current reference price for regular gasoline, which is $3.99/gallon. EPA updates that reference periodically rather than tracking live pump prices, so treat it as a window-sticker estimate rather than today's pump number.

The table below scales the EPA's number to three common driving patterns. The combined MPG and the reference fuel price stay constant, only the annual mileage changes. To get a current-prices estimate, take your local gas price and multiply by 789.5 gallons (the car's annual consumption at the rated MPG).

Compare against other Standard Pickup Trucks 2WD for 2026

If you are cross-shopping the 2026 GMC Sierra 2WD with Sport Mode, the most useful comparison is against the other cars in the Standard Pickup Trucks 2WD class for the same model year. The list below shows the highest-MPG peers, ranked from most to least efficient. Click any of them to open its full page.

The Tesla Cybertruck Long Range (20in Cyber wheels) leads this group at 78 MPG, 59 MPG ahead of the 2026 GMC Sierra 2WD with Sport Mode.

Specifications

The 2026 GMC Sierra 2WD with Sport Mode runs a 2.7-liter 4-cylinder turbocharged engine paired with a automatic 8-spd, sending power through rear-wheel drive.

Engine, transmission, and drivetrain together drive most of the variation in fuel economy across trims. A larger engine moves the car with less effort but burns more fuel. A turbo lets a small engine punch above its weight, often without much MPG penalty. All-wheel drive adds traction and weight, and usually costs a couple of MPG compared with two-wheel drive of the same engine.

Vehicle class

Standard Pickup Trucks 2WD

Engine

2.7L 4-cylinder turbocharged

Transmission

Automatic 8-spd

Drivetrain

Rear-Wheel Drive

Fuel type

Regular

Annual petroleum use

15.7 barrels per year

Start-stop system

Yes

Common questions about the 2026 GMC Sierra 2WD with Sport Mode

Quick answers to the questions people most often search for when looking up the 2026 GMC Sierra 2WD with Sport Mode.

• Is the 2026 GMC Sierra 2WD with Sport Mode fuel efficient?

  Not particularly. The 2026 GMC Sierra 2WD with Sport Mode returns 19 combined MPG, which trails the average car in the Standard Pickup Trucks 2WD class for the same model year by about 22%.
• What MPG does the 2026 GMC Sierra 2WD with Sport Mode get?

  The EPA rates the 2026 GMC Sierra 2WD with Sport Mode at 19 combined MPG, 17 MPG in city driving, and 21 MPG on the highway. Real-world numbers depend on your driving style, the weather, and how loaded the car is.
• How much does it cost to fuel a 2026 GMC Sierra 2WD with Sport Mode per year?

  The EPA estimates an annual fuel cost of $3,150 for the 2026 GMC Sierra 2WD with Sport Mode. That figure assumes 15,000 miles of driving per year, a 55% city and 45% highway split, and the EPA's published average fuel price for the rated fuel grade.
• What fuel does the 2026 GMC Sierra 2WD with Sport Mode use?

  The EPA lists the 2026 GMC Sierra 2WD with Sport Mode as running on regular gasoline. Using a different grade than the manufacturer specifies can affect fuel economy and engine longevity.
• How much CO₂ does the 2026 GMC Sierra 2WD with Sport Mode emit?

  Tailpipe CO₂ emissions are 472 g/mi. Multiplied across a typical year of driving (15,000 miles) that works out to about 7,080 kilograms of CO₂.
• What is the difference between the city and highway MPG of the 2026 GMC Sierra 2WD with Sport Mode?

  City driving returns 17 MPG and highway driving returns 21 MPG, a gap of 4 MPG. The two figures are close enough that the car will hold its rated efficiency well across most driving patterns.
• What engine is in the 2026 GMC Sierra 2WD with Sport Mode?

  The 2026 GMC Sierra 2WD with Sport Mode has a 2.7-liter 4-cylinder turbocharged engine (EPA description: SIDI). Smaller turbocharged engines like this one tend to deliver bigger-engine power on demand while keeping fuel economy closer to a non-turbo version of the same displacement.
• What transmission and drivetrain does the 2026 GMC Sierra 2WD with Sport Mode have?

  The 2026 GMC Sierra 2WD with Sport Mode comes with a automatic 8-spd transmission and rear-wheel drive.
• How does the 2026 GMC Sierra 2WD with Sport Mode compare to the best car in its class?

  The most efficient car in the Standard Pickup Trucks 2WD class for the 2026 model year is the Tesla Cybertruck Long Range (20in Cyber wheels) at 78 combined MPG. The GMC Sierra 2WD with Sport Mode returns 19 MPG, a gap of 59 MPG. If you are comparing on fuel economy alone, the class leader is worth a look.
• How much more does the 2026 GMC Sierra 2WD with Sport Mode cost in fuel compared to an average car?

  The EPA estimates that over five years, the 2026 GMC Sierra 2WD with Sport Mode will cost about $5,000 more in fuel than an average new vehicle of the same model year. The difference accumulates because the car uses more fuel per mile, not because of any one-off charge at the dealership.

Source: U.S. EPA fuel economy dataset. Annual fuel cost figures assume 15,000 miles of driving per year and a 55% city, 45% highway split. Real-world mileage varies with driving conditions, vehicle maintenance, fuel quality, and driver behaviour.