Four-Wheel Drive - GMC 2007 Sierra 1500 Pickup Owner's Manual

When this light comes on, you can shift to the next
higher gear if weather, road and traffic conditions
allow. For the best fuel economy, accelerate slowly
and shift when the light comes on.
While you accelerate, it is normal for the light to
go on and off if you quickly change the position of
the accelerator.
If your vehicle has four-wheel drive and has a
manual transmission, disregard the shift light when
the transfer case is in Four-Wheel Low.
Ignore the shift light when you downshift.

Four-Wheel Drive

If your vehicle has four-wheel drive, you can send
your engine's driving power to all four wheels
for extra traction. To get the most satisfaction out
of four-wheel drive, you must be familiar with
its operation. Read the part that follows before
using four-wheel drive. See the appropriate text for
the transfer case in your vehicle.
While driving on clean dry pavement and during
tight turns, you may experience a vibration in
the steering system.
Front Axle Locking Feature
The front axle locks and unlocks automatically
when you shift the transfer case. Some delay for
the axle to lock or unlock is normal.
Manual Transfer Case
The transfer case shift lever is located on the floor
to the right of the driver. Use this lever to shift
into and out of four-wheel drive.
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