Windows
WARNING
Leaving children, helpless adults, or pets in a vehicle with the windows closed is dangerous.
They can be overcome by the extreme heat and suffer permanent injuries or even death from heat stroke. Never leave a child, a helpless adult, or a pet alone in a vehicle, especially with the windows closed in warm or hot weather.

The vehicle aerodynamics are designed to improve fuel economy performance. This may result in a pulsing sound when either rear window is down and the front windows are up. To reduce the sound, open either a front window or the sunroof (if equipped).
See also:
How to Inspect the Engine Air Cleaner/Filter
To inspect the air cleaner/filter, remove the engine air cleaner/filter from the vehicle by following Steps 1 through 6. When the engine air cleaner/filter is removed, lightly shake it to release loos ...
All Terrain chassis and suspension
Based on the chassis of the 2011 Sierra HD trucks, the All Terrain HD
features a fully boxed steel frame with exceptional strength and torsional
stiffness. It incorporates the production models' n ...
Steering, Suspension, and Chassis Components
Visually inspect front and rear suspension and steering system for damaged, loose,
or missing parts or signs of wear. Inspect power steering lines and hoses for proper
hook-up, binding, leaks, cra ...





