Installation Procedure

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Installation Procedure
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
  1. If reusing the old fasteners, apply sealant GM P/N 12346004, (Canadian P/N 10953480), or equivalent to the threads of the water pump bolts.
  2. Install NEW water pump gaskets and the water pump.
    NOTE: Refer to FASTENER NOTICE .
  3. Install the water pump bolts.

    Tighten 

    Tighten the bolts to 45 N.m (33 lb ft).

    Fig 1: Install Water Pump, Gaskets & Bolts
    G02109202Courtesy of GENERAL MOTORS CORP.
  4. Using J 41240,  hold the water pump pulley, install the water pump pulley bolts.

    Tighten 

    Tighten the bolts to 25 N.m (18 lb ft).

    Fig 2: Install Water Pump Pulley Bolts Using J 41240
    G02109203Courtesy of GENERAL MOTORS CORP.
RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.