Help keep your diesel's emissions system working in cold weather with the Dorman - OE Solutions Diesel Exhaust Fluid (DEF) Heater, part number 904-394, an OE FIX design built to address a known factory failure point. It fits many vehicles, among them the 2012-2016 Chevrolet Silverado 2500 HD, 2012-2016 Chevrolet Silverado 3500 HD and 2012-2016 GMC Sierra 2500 HD. See the "Vehicles it fits" section for the full list and engine details.
On certain vehicles, the factory DEF heater often fails because fluid gets inside it. This Dorman DEF heater changes the OEM design to address that failure point and is intended to improve reliability. A DEF heater warms the diesel exhaust fluid so the fluid stays usable in low temperatures.
- Upgraded replacement: adds protection against fluid intrusion.
- Direct fit: designed to install and work like the original equipment part on the listed applications.
- Thoroughly tested: every design goes through cyclical heater element fatigue testing.
- Engineering support: backed by a team of engineers in the United States.
Signs this part may need replacing include a DEF system warning message or a stored DEF heater trouble code. Other faults can cause the same signs, so diagnose the system first. If the original heater has failed, 904-394 replaces it.
Interchange: 22872118 · 22902620 · 23379348 · 84412924 · DFH106
This part cross-references / interchanges with the following part numbers:
22872118, 22902620, 23379348, 84412924, DFH106
Frequently Asked Questions
What does a diesel exhaust fluid heater do?
It warms the diesel exhaust fluid in the DEF system so the fluid stays usable in cold temperatures. Part 904-394 replaces the original heater on the listed applications.
Does this fit the 2012-2016 Chevrolet Silverado 2500 HD?
Yes. 904-394 is a direct-fit replacement for the 2012-2016 Chevrolet Silverado 2500 HD and 3500 HD. See the "Vehicles it fits" section for the full list and engine details.
How is this different from the factory DEF heater?
Dorman's OE FIX design changes the original to add protection from fluid intrusion, which often causes the factory heater to fail on certain vehicles.
What are signs the DEF heater may need replacing?
A DEF system warning or a stored DEF heater trouble code can signal a heater problem, but other faults can cause them too. Diagnose the system before replacing the heater.
How is this heater tested?
Each design goes through cyclical heater element fatigue testing. The part is backed by a team of engineers in the United States.
