See also:

All-Wheel Drive
If your vehicle is equipped with all-wheel-drive, this is an additional system that needs lubrication. Transfer Case When to Check Lubricant It is not necessary to regularly check the transfe ...

Engine Coolant Heater
Vehicles with the engine coolant heater can use this option in cold weather conditions at or below −18°C (0°F) for easier starting and better fuel economy during engine warm-up. Plug i ...

Diagnostics
OnStar Vehicle Diagnostics will perform a vehicle check every month. It will check the engine, transmission, antilock brakes, and major vehicle systems. It also checks the tire pressures, if the v ...