The 2023 GMC Sierra Cab Chassis 2WD 5.3L gets 16 MPG combined. It won’t win any awards for using less gas, but for contractors, upfitters, and businesses needing a durable, customizable work platform, fuel economy is often lower on the priority list than capability and long-term reliability. This Sierra isn’t designed for running errands; it’s built for hauling and specialized applications, and its efficiency reflects that.

City and highway performance

The EPA numbers reveal more detail. The 15 MPG city rating reflects the energy demands of stop-and-go driving, increased by the vehicle’s weight and the inherent inefficiencies of a large displacement V8. The 18 MPG highway figure is somewhat better, suggesting that when cruising at a steady speed, the Sierra can achieve respectable fuel economy. It is important to understand both figures, as the type of work the truck performs will heavily influence which rating is more relevant. A Sierra spending most of its time navigating urban job sites will likely see figures closer to 15 MPG, while one used primarily for longer distance deliveries might approach 18 MPG.

Annual fuel cost

According to the EPA, the estimated annual fuel cost for the 2023 GMC Sierra Cab Chassis 2WD 5.3L is $2,750. This calculation is based on driving 15,000 miles per year and using the EPA’s projected national average fuel prices. Keep in mind that this is just an estimate. Actual fuel costs will vary depending on individual driving habits, local fuel prices, and the specific demands placed on the vehicle. For example, consistent heavy towing or frequent idling will undoubtedly increase that annual cost.

Real-world expectations

The EPA numbers provide a baseline, but owner reports often paint a more realistic picture. Many report that achieving the EPA’s 18 MPG highway rating is possible when unloaded and driven conservatively. However, adding a heavy service body, tools, or regularly towing will significantly decrease fuel economy. Don’t be surprised to see average MPG figures in the low teens under heavy use. The 10-speed automatic transmission does its best to keep the engine in its optimal range, but ultimately, physics dictate the outcome when moving a substantial weight.

How it compares

Compared to its rivals, the fuel economy of the 2023 GMC Sierra Cab Chassis 2WD 5.3L is largely similar to the competition. A similar Ford F-350 XL regular cab with the 6.2L V8 achieves roughly comparable MPG figures, around 15 MPG combined. Ram’s 3500 Tradesman chassis cab with the 6.4L Hemi similarly demonstrates fuel economy in this range. These trucks aren’t chosen for their Prius-like efficiency. Buyers in this segment prioritize factors such as payload capacity, upfitting options, and overall durability. While there ARE optional diesel powertrains that deliver better fuel economy, the upfront cost and maintenance considerations often lead buyers back to the gasoline V8, regardless of the MPG tradeoff. See all Gmc fuel economy data on this website.

Tips to maximize efficiency

Gentle acceleration and smooth braking can noticeably improve fuel economy. This is particularly true for a heavy vehicle like the Sierra Cab Chassis. Avoid sudden bursts of speed, and anticipate traffic flow to minimize hard braking. Every bit of energy wasted through harsh driving translates directly into wasted fuel.

Proper tire inflation is critical for both safety and fuel efficiency. Check your tire pressures regularly and maintain them at the recommended levels listed on the door jamb sticker. Underinflated tires create more rolling resistance, which increases fuel consumption. Regularly inflate your tires to the correct PSI, especially when carrying heavy loads.

Minimize idling time. Even though modern engines are more efficient at idle than older designs, excessive idling still wastes fuel. If you anticipate being stopped for more than a minute, turn off the engine. This is especially important during cold weather, as extended idling does little to warm up the engine and instead burns unnecessary fuel. Consider that over a vehicle’s lifespan, the wasted gas can add up to a sizable amount.

Plan your routes strategically to avoid congested areas and minimize stop-and-go driving. Use navigation apps to find the most efficient paths, and consolidate multiple trips into one whenever possible. Also, consider if you’re really in the best vehicle for local trips. If running errands on the weekend, take a smaller car if possible. The SIERRA MPG across all years provides some context for this vehicle’s eco footprint vs alternatives.

Reduce aerodynamic drag. While a cab chassis isn’t exactly known for its sleek design, anything you can do to improve airflow can help. Make sure any aftermarket equipment that you add doesn’t disrupt airflow needlessly. Aerodynamic resistance is only noticed at higher speeds, but this has a real influence on highway driving habits.