How large is a Chevy Suburban gas tank?

The typical fuel tank capacity for most Chevy Suburban models in recent years is 31 gallons (about 117 liters).

That size is common across many modern Suburban configurations, but the exact capacity can vary slightly by model year, trim, and engine. For precise figures on a specific vehicle, always check the official spec for that exact build.

Tank size in modern Suburbans

Before examining variability, here are the core details you’re most likely to encounter in current production Suburbans.

• 31 gallons (approximately 117 liters) is the typical capacity for most gasoline Suburban models in recent years.


• Range per tank depends on engine choice and driving conditions; with highway cruising and efficient driving, many drivers see multiple hundreds of miles per tank.

Because exact capacity can vary by year and trim, verify the precise figure for your specific vehicle using the owner's manual or the vehicle’s official spec sheet.

Verifying the fuel tank size for your vehicle

If you’re assessing a particular Suburban—whether new, used, or a custom build—confirming the exact tank size is important for planning fuel stops and range estimates.

• Check the owner's manual or GM’s official spec sheet for your model year and trim.


• Look at the fuel door sticker or the VIN-based build sheet, which can show the precise tank capacity for that configuration.

Verifying these details helps ensure accurate fuel planning, especially when comparing different model years or trims.

Summary

The Chevy Suburban’s gas tank is typically around 31 gallons (about 117 liters) for modern gasoline models, providing substantial range for long trips and towing. While this is the standard in the current generation, some older years or specific configurations may vary slightly, so checking the exact specification for your vehicle is always best.

How many miles per gallon does a 5.3 Suburban get?

A Chevrolet Suburban with a 5.3L engine gets an average of 15 mpg city/19-20 mpg highway, with combined ratings around 16-18 mpg, depending on the model year and drivetrain. For example, a 2023 model with rear-wheel drive gets 15 city/20 highway mpg, while a 4WD model gets 15 city/19 highway mpg. Real-world results can vary, with some drivers reporting slightly higher highway mileage.
 
This video demonstrates the fuel economy of a 2023 Chevrolet Suburban with a 5.3L engine on a highway loop: 1mJimmy's GarageYouTube · May 23, 2023
EPA-estimated MPG by model year and drivetrain:

• 2023 Chevrolet Suburban with 5.3L V8:
  • 2WD: 15 mpg city / 20 mpg highway 
  • 4WD: 15 mpg city / 19 mpg highway 
• 2019 Chevrolet Suburban with 5.3L V8:
  • 2WD: 15 mpg city / 22 mpg highway 
  • 4WD: 14 mpg city / 21 mpg highway 

Factors that affect real-world mileage:

• Driving style: Aggressive acceleration and braking can lower fuel economy, while smooth driving can improve it. 
• Driving conditions: City driving with frequent stops and starts will result in lower MPG than steady highway cruising. 
• Vehicle load: Carrying heavy passengers or cargo will reduce fuel efficiency. 
• Tire size: Larger wheels or tires can have a negative impact on mileage. 
• Maintenance: Proper vehicle maintenance is crucial for optimal fuel efficiency. 

This video compares the fuel costs of a 5.3L engine with a 3.0L diesel engine: 57sMyks GarageYouTube · Mar 22, 2025

How many miles can a Suburban go on a full tank?

A Chevrolet Suburban's range on a tank of gas varies significantly, but it can be up to 728 miles for a modern diesel model on the highway, while gasoline models are typically in the 400–550 mile range. The specific mileage depends on the model year, engine, and driving conditions, with modern gasoline V8s around 550 miles, modern diesel versions exceeding 700 miles, and older or city-driven models having a shorter range. 
Estimated range by engine and model year

• Modern Diesel (e.g., 2023–2025): With a 3.0-liter turbo-diesel, the Suburban can achieve up to 728 miles of highway driving on a single tank. 
• Modern Gasoline (e.g., 2023–2025): Models with a V8 engine can have a range of over 550 miles on the highway. 
• Older Models (e.g., 1998): An older Suburban with a 42-gallon tank could get around 400–450 miles, though this was heavily dependent on driving conditions. 
• City vs. Highway: You will get significantly fewer miles on a tank in stop-and-go city traffic compared to highway driving. For example, one user estimated around 300 miles for 80% city driving, while another noted their mileage drops from over 20 mpg to under 15 mpg in city conditions. 

Factors that affect range

• Engine: The type of engine (diesel vs. gasoline, specific V8 size) makes a big difference. 
• Driving Conditions: Highway cruising is far more fuel-efficient than city driving. 
• Speed: Driving at higher speeds, especially over 60 mph, can dramatically decrease your range. 
• Vehicle Load: Carrying heavy loads or towing can significantly reduce fuel economy. 
• Maintenance: Proper tire inflation and keeping up with maintenance can help maximize your miles per gallon. 

How many gallons of gas does a Suburban hold?

A Chevrolet Suburban holds 28 gallons of gas for most recent models, but some older or long-wheelbase models may have a 31-gallon tank. The exact capacity depends on the specific year and trim level. 

• Most modern Suburbans: 28 gallons 
• Some older/long-wheelbase models: 31 gallons 
• To be certain: Check your owner's manual or look for the tank capacity specification for your exact model year. 

How big is the gas tank on a 2018 Chevy Suburban?

The 2018 Chevrolet Suburban has a fuel tank capacity of approximately 31 gallons. While most sources agree on this number, it's best to check your owner's manual or a vehicle-specific sticker to confirm for your exact configuration. 

• Standard capacity: The most commonly cited size is 31 gallons. 
• Confirmation: If you are unsure about your specific model, you can confirm the tank size in your owner's manual or by checking the vehicle's documentation, notes Reddit users.