Dorman 555-054 Engine Expansion Plug

Dorman 555-054 Engine Expansion Plug

Dorman 555-054 is a steel reverse taper cup engine expansion plug built to match the fit and function of the original core plug on specified Ford and Mercury applications. It is engineered for reliable sealing in the engine block and is a direct replacement for vehicles that use a 2.375-inch steel shallow cup design.

Key Features

• Steel construction for engine block service
• Reverse taper cup design for OE-style fitment
• Maximum diameter: 2.385 in.
• Minimum diameter: 2.388 in.
• Direct replacement for specified Ford and Mercury engine core plug applications
• Part number: 555-054

Detailed Description

This engine core plug is made to match the original part’s fit and function on selected vehicles, including Ford Mustang, Ford Thunderbird, Ford F-100, Ford F-150, Ford F-250, Ford F-350, and several Mercury models. The steel reverse taper cup construction supports a secure seal in the engine block where a worn or leaking expansion plug can affect cooling system integrity. Dorman 555-054 is also cross-referenced to 353001S and EPC-92 for the same application.

What It Helps Address

• Coolant leakage from a deteriorated engine core plug
• Loss of sealing at the engine block expansion plug opening
• Corrosion-related failure of the original steel plug
• Service replacement needs on Ford and Mercury engine blocks
• Fitment issues when replacing a shallow cup style plug

Installation Notes and Tips

Verify the engine block opening size and plug style before installation. This part is listed for specific Ford and Mercury applications, including 1958-1970 Ford Thunderbird, 1967-1970 Ford Mustang, 1975-1976 Ford F-Series trucks, and 1961-1970 Mercury Colony Park, Cougar, Marauder, Marquis, Montego, and Villager applications. Confirm the correct engine core plug location and clean the bore thoroughly before installing the new plug.

Quality Assurance

Dorman manufactures this expansion plug to match original part fit and function on the listed vehicles. The steel construction and OE-style reverse taper cup design support consistent service replacement performance for engine block sealing.