Dorman 904-100 Engine Air Intake Heater Relay

Dorman 904-100 Glow Plug Relay Overview

The Dorman 904-100 is an engine air intake heater relay for diesel applications, built to match the original relay’s fit and function on specified vehicles. It uses a 4-terminal, blade-style, male connection layout with a plug-in mount and a 100-amp rating for direct replacement service.

Compatible with 2001-2004 Chevrolet Silverado 2500 HD, 2001-2004 Chevrolet Silverado 3500, 2001-2004 GMC Sierra 2500 HD, and 2001-2004 GMC Sierra 3500, this relay is a practical OE-style replacement for diesel glow plug control needs.

Key Features

• Direct replacement glow plug relay for specified diesel applications
• Part number 904-100 for easy identification and ordering
• 4-terminal blade design with male terminals
• Plug-in mounting style for straightforward electrical connection
• 100-amp amperage rating
• Plastic cover construction
• Compact size for underhood relay placement

Detailed Description

Dorman 904-100 is engineered to replicate the original relay’s fit and function on supported Chevrolet Silverado and GMC Sierra diesel trucks. The relay’s blade terminals, plug-in mounting style, and 100-amp rating align with the electrical demands of glow plug control systems, helping maintain proper heater relay operation during cold starts. If you are replacing a worn or failed glow plug relay on a 2001-2004 Chevrolet Silverado 2500 HD, Silverado 3500, Sierra 2500 HD, or Sierra 3500, this part number 904-100 provides a direct-fit service solution.

This part cross-references Standard Ignition RY-1666 for the same application.

What It Helps Address

• Hard starting in cold weather on diesel trucks
• Intermittent or inoperative glow plug relay operation
• Delayed intake heater activation during startup
• Electrical relay failure caused by age or heat cycling
• Restoring proper glow plug circuit control on supported vehicles

Installation Notes and Tips

Verify connector style, terminal count, and amperage rating before installation. This relay uses a plug-in mount and male blade terminals, so the vehicle connector should match the original configuration. Confirm fitment by year, make, and model before replacing the existing relay with Dorman 904-100.

Quality Assurance

Dorman designs this diesel glow plug relay to match original equipment fit and function and to provide durable, reliable performance in specified applications. It is a direct replacement option for 2001-2004 Chevrolet Silverado 2500 HD, Silverado 3500, GMC Sierra 2500 HD, and Sierra 3500 diesel trucks.