Dorman 555-027 Engine Expansion Plug - Rear
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Dorman

Dorman 555-027 Engine Expansion Plug - Rear

Brand Dorman 555-027
Position Rear
Describe Type Cup Type
Material Steel
Maximum Diameter 1.514
Minimum Diameter 1.5
Package Contents Expansion Plug
Fits Chevrolet, GMC, Fiat, and Buick · 19 vehicles

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

Steel construction. Built from quality material for reliable performance.

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

Cross-references Gates 31566, Motorad 260-180 and 94023985 for the same application. See all 4.

$32.69Free shipping
In stock · usually ships same day before 1pm CST
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Step 2 — Quantity
Order total $32.69
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Free returns within 60 days if it doesn't fit when fitment is verified.
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Dorman 555-027 Engine Expansion Plug

Dorman 555-027 is a steel cup-type engine expansion plug made to match the fit and function of the original plug on specified vehicles. It is built for rear engine core plug service where a precise diameter and reliable seal matter.

Key Features

  • Steel construction for durable engine block sealing
  • Cup-type design for a direct OE-style replacement
  • Maximum diameter: 1.514 in.
  • Minimum diameter: 1.5 in.
  • Engine core plug for rear installation locations
  • Part number: 555-027

Application Details

This engine expansion plug is designed for rear engine core plug service on select Chevrolet S10, Chevrolet S10 Blazer, Chevrolet LUV, GMC S15, and GMC S15 Jimmy applications. It is a direct-fit replacement for vehicles that call for a 1.50-inch rear cup-type expansion plug, including Fits 1982-1985 Chevrolet S10, rear; Fits 1983-1984 Chevrolet S10 Blazer, rear; and Fits 1975-1981 Chevrolet LUV, rear.

This part cross-references Gates 31566 for the same application.

Common Repair Uses

  • Replacing a leaking or corroded rear core plug
  • Restoring coolant sealing at the engine block
  • Addressing coolant loss from a worn expansion plug
  • Repairing rust-damaged steel plug surfaces
  • Servicing an engine during cooling system maintenance

Installation Notes

Verify the engine block opening measures between 1.5 in. and 1.514 in. before installation. Clean the bore thoroughly and inspect the sealing surface for corrosion or damage so the plug seats evenly. Confirm rear position and vehicle application against the listed fitment for Chevrolet S10, GMC S15, and related models before assembly.

Quality Assurance

Dorman designs this expansion plug to match original part fit and function on specified vehicles. The steel construction and OE-style cup design support dependable service in engine cooling system repairs.

This part fits 19 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelLitersCylindersPositionNotes
1985ChevroletS101.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1985GMCS151.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1984ChevroletS101.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1984ChevroletS10 Blazer1.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1984GMCS151.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1984GMCS15 Jimmy1.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1983ChevroletS101.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1983ChevroletS10 Blazer1.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1983GMCS151.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1983GMCS15 Jimmy1.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1982ChevroletS101.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1982GMCS151.9LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1981ChevroletLUV1.8LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1980ChevroletLUV1.8LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1979ChevroletLUV1.8LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1978ChevroletLUV1.8LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1977ChevroletLUV1.8LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1976ChevroletLUV1.8LL4Rear1.50 In.; 1 Required; Package Quantity: 10; Dorman - AutoGrade - Boxed; Packaging Type: Box
1975ChevroletLUV1.8LL4Rear1.50 In.; 1 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.
Gates — 31566Motorad — 260-18094023985EPC-85