Engine Coolant Heater
The engine heater can provide easier starting and better fuel economy during engine warm-up in cold weather conditions at or below −18°C (0°F). Vehicles with an engine heater should be plugged in at least four hours before starting.
An internal thermostat in the plug-end of the cord may exist which will prevent engine coolant heater operation at temperatures above −18°C (0°F).
If the vehicle has a diesel engine, see the Duramax Diesel supplement for more information.
See also:
Roof Rack System
WARNING
If something is carried on top of the vehicle that is longer or wider than the
roof rack—like paneling, plywood, or a mattress—the wind can catch it while the
vehicle is being driven. ...
Shifting Into Four-Wheel Drive Low
When Four-Wheel Drive Low is engaged, vehicle speed should be kept below 72 km/h (45 mph).
Extended high-speed operation in Four-Wheel Drive Low may damage or shorten the life of the drivetrain.
To ...
Safety
The National Highway Traffic Safety Administration gave the 2007 Yukon a
five-star frontal crash-test rating; it hasn't done a side-impact test as of
this writing. Rollover ratings were listed at ...