100000 MI or 160000 KM

Lubricate
    Steering and Suspension
      Lubricate the front suspension, ball joints, steering linkage, transmission shift linkage, transfer case shift linkage, parking brake cable guides, and brake front axle. Ball joints should not be lubricated unless their temperature is -12 degrees C (10 degrees F) or higher or they could be damaged.
Inspect
    Ignition Cable
Replace
    Spark Plug
    Oil Filter, Engine
    Fluid Filter - A/T
      Vehicles with Allison transmission replace the external spin-on filter only. The sump filter is only changed during overhaul. TSB 05-00-90-005.
    Fluid - A/T
      Vehicles over 8,600 lbs. GVWR, or with Allison transmission.
    Engine Oil
      Change engine oil and filter as indicated by the GM Oil Life System (or every 10,000 miles 16 000 km, or 12 months, whichever occurs first. Reset the system.