Dorman 579-128 Fuel Tank Lock Ring

Dorman Fuel Tank Lock Ring 579-128

Dorman 579-128 is a direct-match fuel tank lock ring for servicing the fuel sending unit. Built from durable plastic and rubber with a black finish, it is made for a secure fit and includes the gasket or seal needed for the tank opening.

Compatible With Ford F-250 Super Duty, Ford F-350 Super Duty, Ford Excursion, Ford Expedition, and Lincoln Navigator applications across the listed model years, this fuel tank lock ring is a practical replacement when the tank module is removed for repair. The Dorman 579-128 design follows the original part dimensions for reliable sealing and retention.

Key Features

• Direct replacement fuel tank lock ring for sending unit service
• Plastic and rubber construction with black finish
• Includes gasket or seal for the tank opening
• Inside diameter: 6.6 in; outside diameter: 7.2 in
• Lock ring diameter: 6.69 in; thickness and rim width: 1.2 in
• Cross-references Ford F75Z9417BB and LO153 for the same application

Detailed Description

This fuel tank lock ring is engineered as a direct match to the original retaining ring used at the fuel tank sending unit. The Dorman 579-128 helps secure the module in place after service, while the included O-ring supports a proper seal at the tank opening. Its molded dimensions are sized for the specified application, making it a straightforward choice for Ford F-250 Super Duty, Ford F-350 Super Duty, Ford Excursion, Ford Expedition, and Lincoln Navigator fuel system repairs.

What It Helps Fix

• Loose or damaged fuel tank sending unit retention
• Fuel odor caused by a worn tank seal area
• Seal issues after fuel pump or sender service
• Corrosion or cracking in the original lock ring
• Improper seating of the fuel module during reassembly

Installation Notes and Tips

Inspect the tank flange and sender sealing surface before installation. Replace the lock ring whenever the sending unit is serviced, and confirm the ring seats evenly before returning the vehicle to service. Verify application details for your specific Ford or Lincoln model year before ordering.

Quality Assurance

Dorman manufactures this lock ring as a direct-fit replacement built from durable materials for dependable service. The part number 579-128 is designed to match the original fit and function for the listed applications.