What transmission fluid does a 2004 Chevy Silverado 2500HD take?

Answer: It depends on the transmission in the truck. Gasoline models with the 4L80-E automatic use Dexron III/Mercon ATF, while Duramax diesel models paired with the Allison 1000 require Allison TES-389 transmission fluid.

Transmission types in the 2004 Silverado 2500HD

To determine the correct fluid, you first need to identify which transmission is in your truck. The 2004 Silverado 2500HD offered two main setups: a gasoline-powered version with the 4L80-E automatic and a diesel-equipped version with the Duramax engine paired to the Allison 1000 transmission. Use your owner’s manual, the transmission identification plate (often found on the transmission itself or in the glove box), or the VIN to confirm which transmission is installed in your specific truck.

Gasoline-engined models with the 4L80-E automatic

The traditional specification for this transmission has been Dexron III/Mercon ATF. Some newer service notes acknowledge Dexron VI as a permissible cross-compatibility option in certain GM transmissions, but you should verify compatibility for your exact vehicle before using it. Below are the fluid options commonly discussed for the 4L80-E in this truck:

Before listing the fluids, note that the exact approval can vary by vehicle and production date. Always cross-check with the owner’s manual or a GM service bulletin before purchasing.



• Dexron III/Mercon automatic transmission fluid (the conventional specification for the 4L80-E)


• Dexron VI automatic transmission fluid (a newer specification that may be acceptable in some cases; confirm with GM guidance for your VIN)

Concluding: For most 2004 Silverado 2500HD gasoline models with the 4L80-E, Dexron III/Mercon ATF is the standard choice. Dexron VI can be considered only if your manual or GM guidance explicitly allows it for your exact vehicle.

Duramax diesel models with the Allison 1000

The Duramax-equipped 2004 Silverado 2500HD uses the Allison 1000 transmission, which requires a fluid meeting the Allison TES-389 specification. Dexron/Mercon fluids are not appropriate for this transmission, and using the wrong fluid can lead to shifting problems or damage. The main recommended fluid option is:

• Allison TES-389 transmission fluid (the official specification for the Allison 1000)

Concluding: For diesel-powered 2004 Silverado 2500HDs with the Allison 1000, use TES-389 ATF as specified by Allison. If TES-389 isn’t available, contact an Allison-certified service provider for guidance before proceeding with a non-TES-389 fluid.

How to identify your exact transmission

Because the fluid you need hinges on the transmission type, confirming which unit is in your truck is essential. Look for the model code on the transmission pan or a label near the transmission, check the glove box paperwork or VIN (Vehicle Identification Number) lookup, or consult the owner’s manual. If you have the VIN, a GM dealer can verify the correct transmission and fluid specification for your exact vehicle configuration.

When to service or replace transmission fluid

Regular maintenance intervals vary, but many owners service automatic transmissions every 30,000 to 60,000 miles, depending on driving conditions and the specific fluid used. If you’re experiencing rough shifts, slipping, or warning lights, it’s wise to check the fluid level and condition, and consult a qualified technician to confirm the correct fluid type before a drain-and-fill or full flush.

Summary

The correct transmission fluid for a 2004 Chevy Silverado 2500HD hinges on the transmission type. Gasoline models with the 4L80-E use Dexron III/Mercon ATF (with Dexron VI as a potential alternative only if explicitly approved for your VIN). Diesel models with the Duramax engine use the Allison 1000 transmission, which requires Allison TES-389 ATF. Always verify your exact transmission type via the manual, transmission code, or VIN before purchasing fluid, and consult a dealer or Allison/GM service guidance if in doubt.

How much transmission fluid does a 2004 Chevy 2500 hold?

The 2004 Chevy 2500 HD transmission fluid capacity depends on the transmission type: the 4-speed 4L80-E has an initial fill of about 7.7 quarts and a total capacity of 13.5 quarts, while the 5-speed Allison M74 has a drain and refill capacity of 7.4 quarts and a total capacity of 12.7 quarts. For a drain and refill on the 4L80-E, the capacity is approximately 7.7 quarts, while a full overhaul of the Allison M74 requires 12.7 quarts.
 
4-speed 4L80-E transmission

• Drain and refill: 7.7 quarts
• Total capacity (complete overhaul): 13.5 quarts 

5-speed Allison M74 transmission

• Drain and refill: 7.4 quarts (or 7.0 liters)
• Total capacity (complete overhaul): 12.7 quarts (or 12.0 liters) 

Important notes

• Check your vehicle's specific transmission: The capacity varies based on whether your truck has the 4L80-E or the Allison transmission. The Allison is typically found in models with the 6.6L Duramax engine. 
• Fluid type: Use the recommended fluid, which for the 4L80-E is Dexron VI, and for the Allison is also Dexron VI. 
• Initial fill: When performing a drain and refill, start by adding the recommended amount for a service fill (around 7.4-7.7 quarts). Start the engine, shift through all the gears, and then top off the fluid as needed to reach the correct level on the dipstick. 
• Overfilling: Be careful not to overfill, as this can damage the transmission. 

What kind of transmission fluid does a Chevy 2500hd take?

The correct transmission fluid for a Chevy 2500HD depends on the model year and transmission, but for most models, it will be DEXRON-VI Automatic Transmission Fluid (ATF). Newer models with the 10-speed transmission may require a special ULV (Ultra Low Viscosity) fluid, and it's essential to consult your owner's manual or check the vehicle's specific requirements. Always verify the exact specification needed for your vehicle's year and transmission type. 
This video explains the correct transmission fluid type for your Chevy, GMC, Buick or Cadillac: 50sMasterJacksYouTube · Mar 26, 2024
Common transmission fluid types by model year 

• For most models (pre-2020): Use DEXRON-VI automatic transmission fluid. You can use either the genuine ACDelco part or a compatible full synthetic fluid from other brands. 
• For newer models (2020+) with the 10-speed transmission: These often require a special ULV (Ultra Low Viscosity) fluid. 
  • This could be a GM fluid or another ULV fluid that meets the specifications, such as the one recommended by Allison Transmission (TES 668®). 
  • Always confirm the specific requirement for your vehicle's transmission.

You can watch this video to learn how to replace the transmission fluid and filter in a 10-speed transmission: 59sAdventure & RepeatYouTube · Apr 21, 2025
How to confirm the correct fluid

• Check your owner's manual: This is the most reliable way to confirm the exact fluid specification for your vehicle's year and transmission. 
• Look at the transmission dipstick or under the vehicle: Some vehicles may have a label indicating the correct fluid type. 
• Consult a parts store or dealership: You can provide your vehicle's year, make, and model to get the correct fluid part number. 

What transmission fluid does a 2004 4L60E take?

The correct transmission fluid for a 2004 4L60E is DEXRON-VI, which is backward compatible with the older DEXRON-III fluid that was originally recommended for the transmission. Many modern fluids, including multi-vehicle fluids, are also suitable, but DEXRON-VI is the most common recommendation for these vehicles today.
 

• DEXRON-VI: This is the modern, recommended fluid for the 2004 4L60E. It is backward-compatible with DEXRON-III and has improved shear and oxidative stability. 
• DEXRON-III: This was the original fluid specified for these transmissions. While you can still use it, DEXRON-VI is a better choice for improved performance and longevity, especially in a 2004 model. 
• Multi-vehicle fluids: Some brands offer multi-vehicle fluids that are compatible with the 4L60E, but it's best to ensure the product explicitly states compatibility with DEXRON-VI or DEXRON-III. 
• Brand choice: Brand is less important than the fluid type. Many reputable brands offer a fluid that meets the DEXRON-VI specification, including ACDelco, which is a popular choice for GM vehicles. 

Important note: Always check your owner's manual or consult a professional mechanic for the most accurate information regarding your specific vehicle and its maintenance requirements.

What kind of transmission fluid does a 2004 Chevy Silverado 2500 HD take?

1 quart. DEXRON-VI Automatic Transmission Fluid (ATF).