Severe Commercial Use Vehicles Only: Lubricate chassis components every 5 000 km/3,000mi.Have underbody flushing service performed. See "Underbody Maintenance" inExterior Care.
Power Mode Description and Operation
GMLAN and Media Oriented Systems Transport (MOST) Wiring RepairsEngine Heater
The engine heater, if available, can
help in cold weather conditions at or
below −18 C (0 F) for easier
starting and better fuel economy
during engine warm-up. Plug in the
engine heater at least four hours
before starting the vehicle. An
internal thermostat in the plug end
of the cord ...