Special Application Services
• Allison Transmission™ Vehicles Only: Replace external transmission filter at first engine oil change only.
• Vehicles with Dual Wheels: Check dual wheel nut torque at 160 km/100 mi, 1 600 km/ 1,000 mi and 9 700 km/6,000 mi.
• Severe Commercial Use Vehicles Only: Lubricate chassis components every 5 000 km/ 3,000 mi.
• Have underbody flushing service performed once a year.
See also:
Compass Zone
The zone is set to zone eight upon leaving the factory. Your dealer will set the correct zone for your location.
Under certain circumstances, such as during a long-distance, cross-country trip or mov ...
Engine Overheating
If the vehicle has the Duramax® Diesel engine, see the Duramax Diesel Supplement for more information.
The vehicle has several indicators to warn of engine overheating.
There is a coolant temperatu ...
Potential Issues
Some OnStar services are disabled after five days. OnStar cannot perform Remote
Door Unlock or Stolen Vehicle Assistance after the vehicle has been off continuously
for five days. After five days, ...





