Dorman 904-5201 Diesel Exhaust Fluid (DEF) Filler Cap

DEF Filler Cap Replacement

Dorman 904-5201 is a diesel exhaust fluid (DEF) filler cap replacement built to match the original cap’s fit and function on specified vehicles. It is engineered for durable, reliable service in the DEF fill opening, with a retention ring included in the package contents.

• DEF filler cap for diesel exhaust fluid fill points
• Matches OE fit and function on specified applications
• Built for durable, dependable performance
• Package contents include a retention ring
• Part number 904-5201 for easy lookup

Application Details

Compatible With select vehicle applications that use a DEF filler cap, including Ford F-250 Super Duty, Ford F-350 Super Duty, and Ford F-450 Super Duty configurations where this part number is specified. This part cross-references Monroe Shocks & Struts (e.g., 172286, 182286) for the same application. Use 904-5201 when replacing a damaged, missing, or worn DEF cap on the correct OE-style fill neck.

Common Issues This Part Can Address

• Broken or cracked DEF filler cap
• Missing cap at the diesel exhaust fluid fill opening
• Loose cap that no longer seals properly
• Contamination entering the DEF fill area
• Need for an OE-style replacement cap for service repair

Installation Notes

Verify the original cap design and vehicle application before installation. Clean the fill area before fitting the new cap, and confirm the retention ring is seated correctly so the cap stays secured during normal use. For fitment-specific service work, match the replacement to the OE part number 904-5201 and the vehicle’s DEF fill configuration.

Quality Assurance

Dorman designs this DEF filler cap to match original equipment fit and function and to provide reliable performance in diesel emissions service. Part number 904-5201 is a direct-reference replacement for the specified application.