Dorman DEF Injector Gasket for Ford & Ram Trucks — 904-085 Direct-Fit, Durable Seal

This replacement gasket is engineered to match the form and function of the original equipment part so technicians and DIYers can reseal the DEF injector without guesswork. Manufactured from robust materials and validated through vehicle try-on testing, the gasket helps prevent leaks and maintains proper DEF system performance after injector maintenance. Verify fitment with your vehicle using the garage tool before ordering.

How does this gasket restore the DEF injector seal?

The Dorman 904-085 reproduces the OEM gasket shape and sealing surfaces to re-establish a leak-free connection between the DEF injector and its mounting point. Correct sealing prevents DEF loss and helps maintain the injector’s operating environment.

• Exact form replication for consistent compression and sealing
• Durable material resists common DEF exposure and temperature cycles
• Vehicle try-on tested to ensure proper mating with injector components

When should I replace the DEF injector gasket?

Any time the DEF injector is removed or serviced, replace the gasket to ensure a reliable seal and avoid repeated labor. Aging, flattening, or cracking of the original gasket are signs it needs replacement.

• Replace after injector removal or repair
• Swap if original gasket is brittle, flattened, or damaged
• Preventative replacement during DEF system maintenance

Which vehicles does this Dorman gasket fit?

904-085 fits many modern Ford Super Duty and F-Series trucks and a wide range of Ram heavy-duty models across specific model years. Always enter your vehicle trim in the garage tool and confirm the "Confirmed Fit" indicator before purchasing.

• Ford F-150 (2018–2021) and Super Duty F-250–F-750 models (selected years)
• Ram 2500, 3500, 4500, 5500 series (2013–2024 depending on model)
• Check the product page garage tool for exact fitment details and any notes

What are the quality highlights and installation tips?

Dorman leverages over a century in replacement parts to produce components that meet workshop expectations for fit and durability. Simple installation usually accompanies injector service, but follow torque and cleanliness procedures to ensure the gasket seals correctly.

• Manufactured from materials selected for DEF exposure resistance
• Underwent vehicle try-on testing for accurate fitment
• Clean mounting surfaces and follow specified torque when reinstalling

Who is this for: The Dorman 904-085 DEF injector gasket is intended for professional technicians, fleet maintenance managers, and knowledgeable DIY owners who service DEF systems on compatible Ford and Ram diesel trucks. If you’re performing injector removal or maintenance and need a dependable, direct-replacement gasket that mirrors OEM fit and function, this part provides a straightforward sealing solution — just confirm vehicle compatibility before ordering.