Dorman 555-108 Engine Cylinder Head Plug
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Dorman

Dorman 555-108 Engine Cylinder Head Plug

Brand Dorman 555-108
Closed End Diameter 0.633 in
Material Steel
Open End Diameter (in) 0.642 in
Package Contents Cup Type Plug
Fits Geo and Chevrolet · 5 vehicles

OE-style replacement. Matches the fit and function of the original plug.

Steel construction. Built from quality material for reliable performance.

Cup type plug. A direct engine cylinder head plug for sealing applications.

Cross-references EPC212-25 for the same application. See all 1.

$24.39Free shipping
In stock · usually ships same day before 1pm CST
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Order total $24.39
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Free returns within 60 days if it doesn't fit when fitment is verified.
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Dorman 555-108 Engine Cylinder Head Plug

Dorman 555-108 is an engine cylinder head plug built to match the fit and function of the original plug on specified vehicles. Made from steel, it is sized for a precise seal in the cylinder head and is suited for service on Chevrolet Spectrum and Geo Spectrum applications.

Key Features

  • Steel construction for durable engine service
  • Closed end diameter: 0.633 in
  • Open end diameter: 0.642 in
  • Cup type plug design
  • OE-style replacement for specified engine cylinder head applications

Detailed Description

This Dorman engine cylinder head plug is engineered as a direct replacement for the original part used on 1985-1988 Chevrolet Spectrum and 1989 Geo Spectrum models. The steel body and cup type design help provide the correct fit in the cylinder head opening, supporting proper sealing where the original plug has worn, corroded, or been damaged. If you are searching for a Dorman 555-108 cylinder head plug for Chevrolet Spectrum or Geo Spectrum engine repair, this part number is built for those exact applications. This part cross-references EPC212-25 for the same application.

What It Helps Address

  • Leaking or deteriorated cylinder head plug
  • Corrosion at the original plug location
  • Loss of sealing at the engine head opening
  • Replacement needs during engine service or rebuild work
  • Fitment issues from using an incorrect plug size

Installation Notes and Tips

Verify the cylinder head opening dimensions before installation and compare them to the listed closed end and open end diameters. Clean the bore thoroughly so the plug seats evenly, and inspect the surrounding head surface for damage or corrosion before pressing the plug into place. For 1985-1988 Chevrolet Spectrum and 1989 Geo Spectrum vehicles, confirm the engine application matches the original plug style before installation.

Quality Assurance

Dorman designs this cylinder head plug to match the fit and function of the original part on specified vehicles. The steel construction and application-specific sizing support consistent service on Chevrolet Spectrum and Geo Spectrum engine repairs.

This part fits 5 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelPositionNotes
1989GeoSpectrumN/A2 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1988ChevroletSpectrumN/A2 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1987ChevroletSpectrumN/A2 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1986ChevroletSpectrumN/A2 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
1985ChevroletSpectrumN/A2 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed
Directly replaces or cross-references 1 part number
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
EPC212-25