Dorman 555-040 Engine Core Plug
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Dorman

Dorman 555-040 Engine Core Plug

Brand Dorman 555-040
Material Steel
Maximum Diameter 1.953
Minimum Diameter 1.94
Describe Type Cup type
Package Contents Expansion plug
Fits Buick · 2 vehicles

OE direct replacement. Matches the fit and function of the original engine expansion plug.

Steel construction. Built from quality steel for reliable performance.

Cup type design. A practical engine core plug style for dependable sealing.

Cross-references Walker Exhaust 31576, 260-219 and 1339404 for the same application. See all 4.

$33.64Free shipping
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Dorman 555-040 Engine Core Plug

Dorman 555-040 is a steel cup-type engine core plug built to match the fit and function of the original plug on specified vehicles. It is sized for a precise seal in the engine block and is listed for 1951-1952 Buick Roadmaster applications.

Key Features

  • Steel construction for engine block service
  • Cup-type design for a direct replacement profile
  • Maximum diameter: 1.953 in.
  • Minimum diameter: 1.94 in.
  • Engineered to match original part fit and function
  • Fits 1951-1952 Buick Roadmaster, N/A

Detailed Description

This engine expansion plug is designed for the Buick Roadmaster and other specified applications where a cup-style core plug is required. The steel construction supports dependable sealing in the engine block, while the measured diameter range helps ensure the plug seats correctly in the bore. Dorman 555-040 is a practical OE-style replacement for restoring the engine cooling system seal on 1951-1952 Buick Roadmaster models.

This part cross-references Walker Exhaust 31576 for the same application.

Common Uses

  • Replacing a leaking or corroded engine core plug
  • Restoring coolant sealing at the engine block
  • Addressing seepage around a worn cup-type expansion plug
  • Repairing a damaged plug bore during engine service

Installation Notes and Tips

Verify bore diameter before installation and confirm the plug seats evenly in the block opening. Clean the sealing surface thoroughly and inspect the surrounding casting for corrosion or pitting before pressing in the new plug. For fitment, this part is listed for 1951-1952 Buick Roadmaster, N/A.

Quality Assurance

Dorman designs this engine expansion plug to match original part fit and function and manufactures it from quality materials for reliable performance. Part number 555-040 is also referenced by 260-219 and EPC-40.

This part fits 2 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelLitersCylindersPositionNotes
1952BuickRoadmaster5.2LL8N/A3 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1951BuickRoadmaster5.2LL8N/A3 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
Directly replaces or cross-references 4 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
Walker Exhaust — 31576260-2191339404EPC-40