GMC 2004 Sierra - Manual (Page 138)

Electronic Transfer Case
If your four-wheel-drive
vehicle has the electronic
transfer case, the
transfer case switches are
located to the left of the
instrument panel cluster.
Use these switches to shift into and out of four-wheel
drive. You can choose among three driving settings:
Recommended Transfer Case Settings
Transfer Case Settings
Driving Conditions 2HI 4HI 4LO N
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*See Recreational Vehicle Towing on page 4-54 or
Towing Your Vehicle on page 4-53 for further
information.
h
(2HI): This setting is for driving in most street and
highway situations. Your front axle is not engaged
in two-wheel drive.
G
(4HI): This setting engages your front axle to help
drive your vehicle. Use 4HI when you need extra
traction, such as on snowy or icy roads, or in most
off-road situations.
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