GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Caution: Natural gas is highly flammable. In order to reduce the risk of fire and personal injury, keep sparks, flames, and smoking materials away from the vehicle while you perform the Compressed Natural Gas (CNG) fuel system service.

    Caution: The Compressed Natural Gas (CNG) system operates at pressures up to 24820 kpa (3600 psi). Relieve the CNG fuel system pressure before servicing CNG fuel system components in order to reduce the risk of fire and personal injury.

  1. Relieve the CNG fuel system pressure. Refer to Fuel Pressure Relief .
  2. Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  3. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical in the C/K Pickup service manual.

  4. Object Number: 757009  Size: SH
  5. Remove the upper (1) and lower (3) tank cover (2) mounting bolts.
  6. Remove the tank cover (2) from the vehicle.

Installation Procedure


    Object Number: 757009  Size: SH
  1. Install the tank cover (2).
  2. 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.

  3. Loosely install all the tank cover bolts.
  4. Tighten
    Tighten the bolts to 8 N·m (71 lb in).

  5. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical in the C/K Pickup service manual.