See also:

Fuel Additives
To provide cleaner air, all gasolines in the United States are now required to contain additives that help prevent engine and fuel system deposits from forming, allowing the emission control system to ...

Engine Air Cleaner/Filter
If the vehicle has a diesel engine, see “Pickup Models” under “Engine Air Cleaner/Filter” in the Duramax® Diesel Supplement for the correct inspection and replacement procedures. See Engine ...

Electronic Transfer Case
The transfer case knob is located next to the steering column. Use the dial to shift into and out of four-wheel drive. ...