Manual Mode - GMC 2012 Sierra Denali Owner's Manual

M (Manual Mode): This position
lets drivers select the range of gears
appropriate for current driving
conditions. See Range Selection
Mode under Manual Mode on
page 9 37.
Notice: Spinning the tires or
holding the vehicle in one
place on a hill using only the
accelerator pedal may damage
the transmission. The repair will
not be covered by the vehicle
warranty. If you are stuck, do not
spin the tires. When stopping on
a hill, use the brakes to hold the
vehicle in place.
The vehicle has a shift stabilization
feature that adjusts the transmission
shifting to the current driving
conditions in order to reduce rapid
upshifts and downshifts. This shift
stabilization feature is designed to
determine, before making an
upshift, if the engine will be able to
maintain vehicle speed by analyzing
things such as throttle position,
vehicle load, and hill grade. If the
shift stabilization feature determines
that a current vehicle speed cannot
be maintained, the transmission
does not upshift and instead holds
the current gear. In some cases, this
may appear to be a delayed shift,
however the transmission is
operating normally.
The vehicle's transmission
uses adaptive shift controls.
Adaptive shift controls continually
compare key shift parameters to
pre programmed ideal shift
conditions stored in the
transmission's computer. The
transmission constantly makes
adjustments to improve vehicle
performance according to the way
the vehicle is being used, such as
with a heavy load. During this
adaptive shift controls process,
some shifts may feel different as the
transmission determines the best
settings for a particular shift.
Driving and Operating

Manual Mode

Range Selection Mode
On vehicles with a Range Selection
Mode, this feature may be used to
control the vehicle's transmission.
To use this feature, do the following:
1. Move the shift lever to
M (Manual Mode).
2. Press the plus/minus buttons to
upshift or downshift, selecting
the desired range of gears for
current driving conditions.
9-37