How do I know if my Chevy truck is gas or diesel?

Determining whether your Chevy truck is powered by a gas or diesel engine is an important piece of information to know as an owner. This knowledge can help you make informed decisions about maintenance, fuel, and other aspects of your vehicle's operation. In this article, we'll provide a step-by-step guide to help you identify the engine type in your Chevy truck.

Identifying the Engine Type

The easiest way to determine if your Chevy truck has a gas or diesel engine is to check the vehicle's information or identification plates. These are typically located in the driver's side door jamb, under the hood, or on the firewall. Look for a label or plate that lists the engine type, displacement, or other identifying information.

• If the engine displacement is listed in liters (e.g., 5.3L, 6.2L), it's likely a gas engine.


• If the engine displacement is listed in cubic inches (e.g., 350 cu in), it's likely a gas engine.


• If the engine displacement is listed in liters with the word "Diesel" (e.g., 6.6L Duramax Diesel), it's a diesel engine.

Another way to identify the engine type is to look at the fuel filler door or cap. Diesel fuel filler doors are typically larger than those for gasoline, and they may have a label indicating "Diesel Fuel Only".

Checking the Exhaust

The sound and appearance of the exhaust can also provide clues about the engine type. Diesel engines typically have a louder, more pronounced exhaust note compared to gas engines. Additionally, diesel exhaust may appear thicker or more opaque than gasoline exhaust.

Consulting the Owner's Manual

If you're still unsure about your Chevy truck's engine type, consult the owner's manual. This document should provide detailed information about the specific engine in your vehicle, including the displacement, fuel type, and other relevant details.

Knowing whether your Chevy truck has a gas or diesel engine is an important piece of information that can help you maintain and operate your vehicle more effectively. By following the steps outlined in this article, you can easily determine the engine type and make informed decisions about your truck's maintenance and operation.

How do I tell what engine is in my truck?

You can find your truck's engine by checking the Vehicle Identification Number (VIN), looking at labels under the hood, or by consulting the owner's manual. The VIN, a 17-character code, can be decoded online to reveal engine details. Other methods include finding a label on the engine block itself or checking a plaque on the dashboard or door frame.
 
Method 1: Use the VIN

• Locate the VIN: It is typically found on the driver's side of the dashboard (visible through the windshield), on a sticker on the driver's side door jamb, or under the hood. 
• Find a VIN decoder: Use an online VIN decoder from an auto parts store or the NHTSA to look up your vehicle's specifications. 
• Decode the engine information: The eighth character of the VIN often indicates the engine type. The decoder will provide a detailed report about your engine. 

Method 2: Check under the hood

• Open the hood: With the engine off and cool, open the hood and look for any labels or markings. 
• Look for labels: The engine size (e.g., "3.3L3.3 cap L3.3𝐿") may be on an engine cover or a sticker near the front of the engine bay, sometimes called a "catalyst tag". You may also find an engine family name stamped on a label on the engine block itself. 

Method 3: Consult your owner's manual

• Open your owner's manual: Look for a "Specifications" or "Engine Information" section to find details about your truck's engine. 

How do I know if my truck is diesel or gas?

You can tell if a truck is gas or diesel by checking the fuel filler door for a sticker, as it will either say "Diesel Only" or "Unleaded Gasoline Only". Other visual cues include checking the tachometer for a lower redline (around 5,000 RPM) on a diesel, looking for a "D" in the model name on the exterior, or observing the fuel nozzle and filler neck, where the diesel nozzle is thicker. 
This video demonstrates how to tell the difference between gas and diesel fuel at the pump: 0:47drivingtestsuccessTikTok · Nov 3, 2021
Outside the vehicle

• Fuel door sticker: The most reliable method is to open the fuel door and look for a sticker on the inside that clearly labels the fuel type. 
• Model name: Look for a "D" in the truck's model name, which indicates a diesel engine (e.g., a BMW 540d). 
• Fuel filler neck: The diesel fuel filler neck is wider than the gasoline one, so the nozzle for a gas pump will not fit into a diesel vehicle, and vice-versa. 
• DEF system: A separate, often blue-capped, diesel exhaust fluid (DEF) fill port is another strong indicator of a diesel engine. 

Under the hood 

• Spark plugs: Gasoline engines have spark plugs; diesel engines do not. 
• Engine appearance: Diesel engines typically have larger injectors and a steel pipe running to the fuel injectors in each cylinder head. 

Inside the cabin

• Tachometer: A diesel truck's tachometer will have a lower redline, usually around 5,000 RPM, compared to a gasoline engine's higher redline. 
• Instrument cluster: Some trucks have the fuel type printed on the instrument cluster near the fuel gauge. 

If still unsure

• Owner's manual: Consult the owner's manual, which will have this information in the engine or maintenance section.
• Online search: Search the truck's make, model, and year online to find the specifications. 

How do I know if my Silverado is gas or diesel?

Check the Fuel Cap.
The little door that houses access to your fuel tank should be labeled with 'Unleaded Gasoline Only' or 'Diesel Only' to indicate what kind of fuel the vehicle utilizes. You can also check the size of the fuel filler neck.

Does a Chevy Silverado take gas or diesel?

The Chevy Silverado comes with either gas or diesel engines, and the best choice depends on your needs. Choose gas if you prioritize lower upfront and maintenance costs, or if you don't frequently tow heavy loads. Choose diesel if you need superior towing and hauling capabilities, better long-term fuel efficiency, and higher durability.
 
You can watch this video to compare the towing capabilities of the Silverado 1500 gas and diesel engines: 59sTruck MasterYouTube · Sep 4, 2025
Gas engine

• Best for: Daily driving, occasional towing, lighter duties, and lower initial cost. 
• Pros:
  • Lower upfront cost. 
  • Cheaper and more readily available parts for maintenance. 
  • Quieter operation. 
  • Better acceleration due to higher horsepower (in some configurations). 
• Cons:
  • Less fuel-efficient, especially when towing. 
  • Lower torque, which is less ideal for heavy-duty towing. 

Diesel engine

• Best for: Frequent heavy towing, long-distance driving, and drivers who want maximum durability. 
• Pros:
  • Superior torque for heavy towing and hauling. 
  • Better fuel efficiency, particularly under load. 
  • Longer engine life. 
  • Higher resale value. 
• Cons:
  • Higher initial purchase price. 
  • Potentially higher maintenance costs. 
  • Diesel fuel can be less available in some areas. 

How to decide

• Consider your typical usage: If you mostly drive around town, use it for lighter tasks, and only occasionally tow, a gas engine is likely the more practical and cost-effective choice. 
• Factor in your towing needs: If your work or hobbies require frequently towing heavy trailers or loads, the diesel engine's superior torque and fuel economy make it the better option, despite the higher upfront cost. 
• Evaluate long-term costs: While diesel engines have a higher initial cost, their better fuel economy and longer lifespan can lead to savings over the long run, especially for high-mileage drivers.