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    ACDelco Conventional Spark Plug

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    Exact Fit May Not Fit Doesn't Fit for your

    Warranty Information
    Save $24 By Mail ($3 per plug) when you buy 8 ACDelco, Autolite, or DENSO iridium spark plugs. See Rebates Page for more details on all spark plug offers.
    • Product Details

      Part No. 21025103

      Warranty Details (2 YR REPLACEMENT IF DEFECTIVE)

      ACDelco GM Original Equipment Conventional Spark Plugs are designed, engineered, and tested to rigorous standards, and are backed by General Motors. These Conventional Spark Plugs are designed for reliability and efficient performance, and are a high quality replacement for many vehicles on the road today. Their high-quality copper cores and outstanding suppression characteristics deliver reliable performance. They are also available for Marine applications. These premium aftermarket replacement spark plugs are manufactured to meet your expectations for fit, form, and function. ACDelco GM Original Equipment parts are the true OE parts installed during the production of or validated by General Motors for GM vehicles. Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional.

      Product Features:

      • Black Onyx coating helps reduce corrosion
      • Copper core provides great heat transfer and helps maximize plug durability
      • Ribbed suppressor seal extends resistance and helps prevent spark 'flash over' and misfires
      • Nickel-chrome alloy sheathing helps prevent corrosion on center electrode
      • Available for use in Marine applications
      • Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional
      • ACDelco GM Original Equipment parts are designed, engineered and tested to rigorous standards, and are backed by General Motors
      • GM Engineers design and validate OE parts specifically for your Chevrolet, Buick, GMC, or Cadillac vehicle
      • GM regularly updates production and service part designs to integrate new materials and technologies

    • Specifications
      • Center Electrode Core Material:Copper
        Ground Configuration:Single
        Ground Electrode Quantity:1
        Ground Electrode Tip Design:Single Prong Electrode
        Height:3.54 in
        Hex Size:16mm
        Insulator Height:2.047 in
        Length:3.94 in
        Pre-Gap Size:0.043 in
        Programming Required:No
        Reach:0.748 in
        Resistor Type:Yes
        Seat Type:Gasket
        Thread Diameter:0.551 in
        Weight:.36 lb
        Width:.94 in
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