GM Service Manual Online
For 1990-2009 cars
Makes 🢒 Chevrolet 🢒 2004 🢒 C-Series Medium Duty Truck C6/7/8 - Mexico 🢒 Engine 🢒 Engine Controls - 8.1L 🢒 Fuel Tank Replacement

Removal Procedure
  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  2. Drain the fuel from the tank. Refer to Fuel Tank Draining .
  3. Remove the fuel sender assembly electrical connector.

    4. Object Number: 724691 Size: SH
  4. Remove the fuel feed (1), fuel return (3), and evaporative emission (EVAP) lines from the fuel sender assembly (3). Refer to Plastic Collar Quick Connect Fitting Service .

    5. Object Number: 724681 Size: SH
  5. Remove the fuel tank strap nuts (7) and the washers (8).
  6. Remove the cotter pins, (5) the washers, (4) and pins (3) from the fuel tank bracket.
  7. Remove the fuel tank strap assemblies (9).
  8. Support and slide the fuel tank out.
  9. Remove the fuel sender assembly if replacing or servicing the tank. Refer to Fuel Sender Assembly Replacement .
  10. Purge the tank if the tank is being serviced. Refer to Fuel System Cleaning .

Installation Procedure
  1. Install the fuel sender assembly if replacing or servicing the tank. Refer to Fuel Sender Assembly Replacement .

    2. Object Number: 724681 Size: SH
  2. Slide the fuel tank into position.
  3. Install the fuel tank strap assembles (9) to the fuel tank bracket.
  4. Install the pins (3), the washers (4), and cotter pins (5) to the fuel tank bracket.

    5. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  5. Install the fuel tank strap nuts (7) and the washers (8).

    6. Tighten
    Tighten the nuts to 25 N·m (18 lb ft).

  6. Reconnect the fuel sender assembly electrical connector.

    7. Object Number: 724691 Size: SH
  7. Install the fuel feed (1), fuel return (3), and EVAP lines to the fuel sender assembly (3). Refer to Plastic Collar Quick Connect Fitting Service .
  8. Refill the fuel tank.
  9. Inspect for leaks using the following procedure:
    10. 9.1. Turn the ignition ON for 2 seconds.
    9.2. Turn the ignition OFF for 10 seconds.
    9.3. Turn the ignition ON.
    9.4. Inspect for fuel leaks.