Dorman 904-5555 Diesel Exhaust Fluid (DEF) Injector Gasket

DEF Injector Gasket for Diesel Emissions Service

Dorman 904-5555 is a specific-fit diesel exhaust fluid injector gasket built to match the original equipment shape and sealing function. It is made from steel and sized for a dependable seal during DEF injector service on diesel emissions systems.

For technicians and owners searching for a DEF injector gasket for diesel exhaust fluid injector repair, this replacement part supports clean reassembly and consistent sealing on applications such as Mercedes-Benz Sprinter diesel emissions service. The Dorman 904-5555 is also a direct-fit option for OE-style maintenance where the injector gasket must be renewed after service.

Key Features

• Specific-fit DEF injector gasket for diesel emissions control service
• Steel construction for a stable sealing surface
• Grey finish
• Measures 3.26 in long and 0.35 in thick
• Two mounting holes for OE-style alignment
• Matches the fit and function of the original gasket
• Cross-references A4721420580 for the same application

Detailed Description

This Dorman DEF injector gasket is intended for diesel exhaust fluid injector sealing during emissions system maintenance. The part number 904-5555 is engineered as a direct replacement for the original gasket, helping restore the seal between the injector and its mounting surface after service. Because DEF injector gaskets are exposed to heat, fluid, and repeated service cycles, replacing the gasket during injector work helps maintain proper sealing performance. Mercedes-Benz Sprinter owners and diesel repair shops looking for a replacement DEF injector gasket can use this OE-style part for service work that requires a specific-fit seal.

Common Issues This Part Can Help Address

• DEF seepage around the injector mounting area
• Seal damage found during injector removal or service
• Exhaust aftertreatment leaks at the injector interface
• Reassembly concerns when the original gasket is no longer sealing properly
• Emissions service repairs requiring a fresh injector gasket

Installation Notes and Tips

Replace the gasket any time the DEF injector is serviced. Clean the mating surfaces before installation and verify that the injector and mounting area are free of debris or residue. Confirm specific-fit application details before ordering, especially when servicing Mercedes-Benz Sprinter diesel emissions components. Dorman 904-5555 should be installed as part of a proper DEF injector service procedure.

Quality Assurance

Dorman manufactures replacement parts to match original equipment fit and function, and this gasket is built from quality materials for dependable sealing performance. Part number 904-5555 is a direct replacement option for diesel emissions maintenance where a precise injector gasket seal is required.