144000 MI or 230400 KM

Lubricate
    Steering
      Severe Commercial Use Vehicles Only.
Inspect
    Fuel Tank
      Visual inspection of the CNG fuel tanks by a CSA International-certified inspector or authorized GM dealer. For more information, see your dealer or see: http://www.csa-international.org. Have the CNG fuel system and tanks inspected if the vehicle has been involved in a collision or fire. The fuel tanks must be replaced 15 years after manufacture. The expiration date of the fuel tanks is on a label on the fuel tanks. Have an authorized GM dealer replaced the fuel tanks. Do not reuse old fuel tanks.
Replace
    Fuel Filter
      Replacement of the coalescent filter.