GMC 1999 Envoy Owner's Manual page 81

Tow/Haul Selector Switch
You can use this feature to more efficiently tow or haul a
heavy load. See "Tow/Haul Mode" in the Index for
more information.
Your vehicle is equipped
with a tow/haul selector
switch. This switch is
located on the shift knob.
Four Wheel Drive
-
Because your vehicle has four
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. You should use two
for most normal driving conditions.
NOTICE:
Driving in the 4HI or 4LO positions for a long
time on dry or wet pavement could shorten the
life of your vehicle's drivetrain.
yellowblue
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wheel drive, you can
-
wheel drive (2HI)
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