Dorman 550-017 Engine Cylinder Head Plug
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Dorman

Dorman 550-017 Engine Cylinder Head Plug

Brand Dorman 550-017
Closed End Diameter 1.255 in
Material Steel
Open End Diameter (in) 1.255 in
Package Contents Cup Type Plug
Fits Cadillac · 40 vehicles

OE-style fit. Matches the original part's function for straightforward replacement.

Steel construction. Built from quality material for reliable engine sealing.

Cup type plug. Engine cylinder head plug for sealing an engine opening.

Cross-references 1489745 and EP-11 for the same application. See all 2.

$25.90Free shipping
In stock · usually ships same day before 1pm CST
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Dorman 550-017 Engine Cylinder Head Plug

Dorman 550-017 is an engine cylinder head plug built to match the fit and function of the original plug on specified vehicles. Made from steel with a 1.255 in closed-end diameter and 1.255 in open-end diameter, it is engineered for dependable sealing in the cylinder head.

Compatible with 1976-1981 Cadillac Commercial Chassis, DeVille, Eldorado, Fleetwood, and Seville, this Dorman cylinder head plug supports OE-style service on classic Cadillac engines. The Dorman 550-017 is a direct-fit replacement for applications that call for a cup type plug.

Key Features

  • Steel construction for engine service durability
  • 1.255 in closed-end diameter
  • 1.255 in open-end diameter
  • Cup type plug design
  • Matches the fit and function of the original part on specified vehicles
  • Cross-reference part numbers include 1489745 and EP-11

Detailed Description

This engine cylinder head plug is designed for direct replacement in select Cadillac applications, including 1976-1981 Cadillac DeVille, 1976-1981 Cadillac Eldorado, and 1976-1981 Cadillac Fleetwood. It is also listed for 1976-1981 Cadillac Commercial Chassis and 1976-1981 Cadillac Seville. Built from steel and sized at 1.255 inches on both ends, Dorman 550-017 helps restore proper sealing where the original cylinder head plug has worn, corroded, or failed.

This part cross-references 1489745 and EP-11 for the same application.

Common Uses

  • Replacing a leaking or corroded engine cylinder head plug
  • Restoring cylinder head sealing on classic Cadillac engines
  • Addressing coolant loss caused by plug deterioration
  • Repairing engine service issues tied to an incorrect plug size

Installation Notes and Tips

Verify cylinder head plug diameter and application before installation. Clean the bore thoroughly, inspect the sealing surface for corrosion or damage, and install the plug according to the vehicle service procedure for the specific Cadillac engine. Confirm the plug seats evenly to help maintain a proper seal.

Quality Assurance

Dorman manufactures this replacement cylinder head plug to match original part fit and function for the listed vehicles. The steel construction and OE-style dimensions support reliable service in the specified Cadillac applications.

This part fits 40 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelLitersCylindersPositionNotes
1981CadillacCommercial Chassis6.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1981CadillacDeVille6.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1981CadillacDeVille5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1981CadillacEldorado6.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1981CadillacEldorado5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1981CadillacFleetwood6.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1981CadillacFleetwood5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1981CadillacSeville6.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1981CadillacSeville5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1980CadillacCommercial Chassis6.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1980CadillacDeVille6.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1980CadillacDeVille5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1980CadillacEldorado5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1980CadillacEldorado6.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1980CadillacFleetwood6.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1980CadillacFleetwood5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1980CadillacSeville5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1980CadillacSeville6.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1979CadillacCommercial Chassis7.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1979CadillacDeVille7.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1979CadillacDeVille5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1979CadillacEldorado5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1979CadillacFleetwood7.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1979CadillacFleetwood5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1979CadillacSeville5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1978CadillacCommercial Chassis7.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1978CadillacDeVille7.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1978CadillacEldorado7.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1978CadillacFleetwood7.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1978CadillacSeville5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1977CadillacCommercial Chassis7.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1977CadillacDeVille7.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1977CadillacEldorado7.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1977CadillacFleetwood7.0LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1977CadillacSeville5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1976CadillacCommercial Chassis8.2LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1976CadillacDeVille8.2LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1976CadillacEldorado8.2LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1976CadillacFleetwood8.2LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1976CadillacSeville5.7LV8N/A4 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
Directly replaces or cross-references 2 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
1489745EP-11