2003 GMC Sierra Denali 1500 AWD: MPG and fuel economy

This page collects every fuel-economy figure the EPA publishes for the 2003 GMC Sierra Denali 1500 AWD. 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. If you want to know whether this generation got more or less efficient over the years, the year-over-year table further down covers every model year the EPA has rated.

Fuel economy at a glance

These are the EPA's official ratings for the 2003 GMC Sierra Denali 1500 AWD. 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.

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 2003 GMC Sierra Denali 1500 AWD compares

The 2003 GMC Sierra Denali 1500 AWD returns 13 combined MPG. Cars in the Standard Pickup Trucks 4WD class for the same model year average 14.7 MPG, which puts this car behind the class average by about 12%.

The most efficient car in the Standard Pickup Trucks 4WD class for the 2003 model year is the Toyota Tacoma 4WD at 18 MPG. The bar chart below puts the GMC Sierra Denali 1500 AWD alongside the class best and the class average so you can see the full picture.

For broader context, the average new car of the 2003 model year (across all classes) returns 18.4 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 2003 model year is on its own page.

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 1153.8 gallons (the car's annual consumption at the rated MPG).

Year-over-year MPG for the GMC Sierra Denali 1500 AWD

The EPA has rated the GMC Sierra Denali 1500 AWD across 2 model years, from 2002 GMC Sierra Denali 1500 AWD through 2003 GMC Sierra Denali 1500 AWD. The numbers below are the best combined MPG figure the EPA published for each year, which lets you see when the car was at its most efficient and how recent generations stack up.

Combined MPG has stayed in roughly the same range across the run, hovering close to 13 MPG.

Compare against other Standard Pickup Trucks 4WD for 2003

If you are cross-shopping the 2003 GMC Sierra Denali 1500 AWD, the most useful comparison is against the other cars in the Standard Pickup Trucks 4WD 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 Toyota Tacoma 4WD leads this group at 18 MPG, 5 MPG ahead of the 2003 GMC Sierra Denali 1500 AWD.

Specifications

The 2003 GMC Sierra Denali 1500 AWD runs a 6-liter 8-cylinder engine paired with a automatic 4-spd, sending power through 4-wheel or all-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 4WD

Engine

6L 8-cylinder

Transmission

Automatic 4-spd

Drivetrain

4-Wheel or All-Wheel Drive

Fuel type

Regular

Annual petroleum use

22.9 barrels per year

Common questions about the 2003 GMC Sierra Denali 1500 AWD

Quick answers to the questions people most often search for when looking up the 2003 GMC Sierra Denali 1500 AWD.

• Is the 2003 GMC Sierra Denali 1500 AWD fuel efficient?

  Not particularly. The 2003 GMC Sierra Denali 1500 AWD returns 13 combined MPG, which trails the average car in the Standard Pickup Trucks 4WD class for the same model year by about 12%.
• What MPG does the 2003 GMC Sierra Denali 1500 AWD get?

  The EPA rates the 2003 GMC Sierra Denali 1500 AWD at 13 combined MPG, 11 MPG in city driving, and 15 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 2003 GMC Sierra Denali 1500 AWD per year?

  The EPA estimates an annual fuel cost of $4,600 for the 2003 GMC Sierra Denali 1500 AWD. 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 2003 GMC Sierra Denali 1500 AWD use?

  The EPA lists the 2003 GMC Sierra Denali 1500 AWD 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 2003 GMC Sierra Denali 1500 AWD emit?

  Tailpipe CO₂ emissions are 684 g/mi. Multiplied across a typical year of driving (15,000 miles) that works out to about 10,254 kilograms of CO₂.
• What is the difference between the city and highway MPG of the 2003 GMC Sierra Denali 1500 AWD?

  City driving returns 11 MPG and highway driving returns 15 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 2003 GMC Sierra Denali 1500 AWD?

  The 2003 GMC Sierra Denali 1500 AWD has a 6-liter 8-cylinder engine.
• What transmission and drivetrain does the 2003 GMC Sierra Denali 1500 AWD have?

  The 2003 GMC Sierra Denali 1500 AWD comes with a automatic 4-spd transmission and 4-wheel or all-wheel drive. All-wheel-drive variants typically read 1 to 3 MPG lower than the front-wheel-drive equivalent of the same engine, since the extra hardware adds weight and parasitic loss.
• How does the 2003 GMC Sierra Denali 1500 AWD compare to the best car in its class?

  The most efficient car in the Standard Pickup Trucks 4WD class for the 2003 model year is the Toyota Tacoma 4WD at 18 combined MPG. The GMC Sierra Denali 1500 AWD returns 13 MPG, a gap of 5 MPG. If you are comparing on fuel economy alone, the class leader is worth a look.
• How much more does the 2003 GMC Sierra Denali 1500 AWD cost in fuel compared to an average car?

  The EPA estimates that over five years, the 2003 GMC Sierra Denali 1500 AWD will cost about $12,250 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.