LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Hummer >> 2003 >> H2 >> Repair and Diagnosis >> External Pages >> Different car >> Section 405 (Engine Controls - 8.1L (Introduction)) >> Repair Instructions >> Spark Plug Replacement >> Installation Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Installation Procedure

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
  1. Correctly position the spark plug washer.
    Fig 1: View Of Spark Plug
    GM470690Courtesy of GENERAL MOTORS CORP.
  2. Inspect the spark plug gap. Adjust the gap as needed.

    Specification:  Spark plug gap: 1.524 mm (0.060 in)

  3. Hand start the spark plug in the corresponding cylinder.
    NOTE: Refer to Fastener Notice in Cautions and Notices.
  4. Tighten the spark plug.

    Tighten: 

    • Tighten the plug to 20 N.m (15 lb ft) for USED heads.
    • Tighten the plug to 30 N.m (22 lb ft) for NEW heads.

  5. Install the spark plug wire. Refer to Spark Plug Wire Replacement .
scientia non olet · About LEMON Manuals