GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2008 🢒 Sierra - 2WD 🢒 General Information 🢒 General Information 🢒 Spark Plug Replacement

Removal Procedure

    Object Number: 1876924 Size: SH
  1. Remove the appropriate spark plug wire boot(s) (2) from the spark plug. (left side shown, right similar).
    2. 1.1. Twist the spark plug boot 1/2 turn.
    1.2. Pull ONLY on the spark plug boot or use a tool designed for this purpose in order to remove the spark plug wire boot from the spark plug.

    Object Number: 1876950 Size: SH
  2. Loosen the spark plug 1 or 2 turns. (left side shown, right similar).
  3. Brush or air blast away any dirt from around the spark plug.
  4. Remove the spark plug. If removing more than 1 plug, place each plug in a tray marked with the corresponding cylinder number.

Installation Procedure

    Object Number: 1876950 Size: SH
  1. Ensure that the spark plug washer is positioned correctly.
  2. Inspect the spark plug gap. Adjust the gap as needed. Refer to Engine Mechanical Specifications .
  3. Install the spark plug into the cylinder head by hand. (left side shown, right similar).

    4. Notice: Refer to Fastener Notice in the Preface section.

  4. Tighten the spark plug.

    5. Tighten
    Tighten the plug to 15 N·m (11 lb ft).


    Object Number: 1876924 Size: SH
  5. If reinstalling the old spark plug wires, apply dielectric grease GM PN  12345579 (Canadian PN 10953481), or equivalent to the inside the spark plug wire boots.
  6. Install the appropriate spark plug wire boot(s) (2) to the spark plug. (left side shown, right similar).