Dorman 904-5502 Diesel Exhaust Fluid (DEF) Filler Cap

DEF Filler Cap for Specific Vehicles

This Dorman DEF filler cap is a direct-fit replacement for the original diesel exhaust fluid cap on specified vehicles. Built from blue plastic, it is designed to match OE fit and function for dependable sealing at the DEF fill point.

Part number 904-5502 is a specific-fit component for diesel exhaust fluid service and is a practical choice when the original cap is damaged, missing, or no longer sealing properly. It is also referenced by interchange numbers 572.3001 and 21148725 for the same application.

Key Features

• Direct replacement DEF filler cap from Dorman
• Blue plastic construction
• Specific fit for designated vehicle applications
• Designed to match original cap fit and function
• Package contents include a retention ring and keys
• Part number 904-5502 for catalog and service lookup

Detailed Description

Dorman 904-5502 is a diesel exhaust fluid filler cap engineered for vehicles that use a keyed DEF cap design. The cap is built to align with the original equipment shape and sealing requirements, helping maintain a secure closure at the DEF tank opening. For service departments and owners searching for a blue DEF filler cap, a plastic DEF cap replacement, or a Dorman 904-5502 DEF cap for OE-style service, this part provides a straightforward replacement option.

Use this cap when servicing DEF fill components on applications such as Chevrolet Silverado and GMC Sierra platforms that require the correct keyed filler cap design. The specific-fit construction helps ensure the cap matches the intended vehicle setup rather than a universal design.

What It Helps Address

• Broken or cracked DEF filler cap
• Missing cap at the diesel exhaust fluid fill point
• Improper sealing at the DEF tank opening
• Worn keyed cap that no longer secures correctly
• Need for a direct replacement on specific Chevrolet Silverado and GMC Sierra applications

Installation Notes and Tips

Confirm the vehicle uses the correct keyed DEF filler cap before ordering. Compare the original cap shape, locking style, and connector details to the replacement part number 904-5502. Clean the fill area before installation and verify the cap seats fully and locks as intended after fitting.

Quality Assurance

Dorman designs this DEF filler cap to match the fit and function of the original part on specified vehicles and to provide durable, reliable service in diesel exhaust fluid applications. The included retention ring and keys are listed in the package contents for this part.