Dorman 904-394 Diesel Exhaust Fluid (DEF) Heater

Overview of Dorman Diesel Exhaust Fluid Heater 904-394

The Dorman 904-394 Diesel Exhaust Fluid (DEF) Heater is designed specifically for heavy-duty Chevrolet and GMC trucks. This DEF heater ensures optimal fluid temperature for efficient emission control in cold weather conditions, supporting reliable operation of your Sierra 2500 HD, Sierra 3500 HD, Silverado 2500 HD, or Silverado 3500 HD.

• Specific fit for Chevrolet and GMC heavy-duty trucks
• Plastic black housing with durable construction
• Two electrical connectors with male and female terminals
• Includes mounting hardware for straightforward installation
• Resistor-type level sensor for accurate fluid monitoring
• Female inlet and outlet fittings for secure hose connections
• Wire insulation made of plastic with multiple wire colors for easy identification
• Height dimension of 191 mm and inside diameter of 115 mm

Detailed Product Description

The Dorman 904-394 DEF Heater is engineered to maintain the proper temperature of diesel exhaust fluid in cold environments, preventing crystallization and ensuring consistent DEF flow. Its black plastic housing provides corrosion resistance and durability under engine bay conditions. The heater features two electrical connectors with a combination of male and female terminals, supporting secure and reliable electrical connections. The resistor-type level sensor integrated into the unit helps monitor DEF levels accurately, contributing to the emission system's overall performance. Designed with female inlet and outlet fittings, this heater allows for easy integration with existing DEF lines. The included mounting hardware simplifies installation, making it a direct replacement part for specific Chevrolet and GMC models.

Compatible Vehicles and Applications

This DEF heater is compatible with the following heavy-duty trucks:

• Chevrolet Sierra 2500 HD
• Chevrolet Sierra 3500 HD
• GMC Sierra 2500 HD
• GMC Sierra 3500 HD
• Chevrolet Silverado 2500 HD
• Chevrolet Silverado 3500 HD

Common Issues Addressed by the DEF Heater

• Prevents DEF freezing and crystallization in cold weather
• Maintains proper DEF temperature for emission system efficiency
• Reduces risk of DEF line blockages and pump failures
• Supports accurate DEF level sensing to avoid warning lights
• Helps maintain compliance with emission control regulations

Installation Notes and Tips

The Dorman 904-394 DEF Heater comes with all necessary mounting hardware for a secure fit. Ensure electrical connectors are properly matched to the male and female terminals to avoid connection issues. Verify that the female inlet and outlet fittings align correctly with your vehicle’s DEF lines. It is recommended to inspect wiring insulation and routing to prevent damage from heat or abrasion during installation. Professional installation is advised to maintain system integrity and performance.

Quality Assurance and Warranty

Dorman parts are manufactured to meet or exceed OEM standards, providing reliable performance for emission control components. The 904-394 DEF Heater undergoes rigorous quality checks to ensure durability and functionality. Please refer to Dorman’s warranty policy for specific coverage details on this emission control part.