GMC Savana 2020 Owner's Manual page 175

174 Driving and Operating
Caution (Continued)
the engine to cool the automatic
transmission fluid. This message
clears when the transmission fluid
has cooled sufficiently.
D : This position is for normal
driving. It provides the best fuel
economy. If you need more power
for passing, and you are:
Going less than about 55 km/h
(35 mph), push the accelerator
pedal about halfway down.
Going about 55 km/h (35 mph) or
more, push the accelerator all
the way down.
By doing this, the vehicle shifts
down to the next gear and has
more power.
D (Drive) can be used when towing
a trailer, carrying a heavy load,
or driving on steep hills. You might
want to shift the transmission to a
lower gear selection if the
transmission shifts too often.
Downshifting the transmission in
slippery road conditions could result
in skidding. See Skidding under
Loss of Control 0 155.
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 is able to
maintain vehicle speed by analyzing
things such as vehicle speed,
throttle position, and vehicle load.
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 could appear to
be a delayed shift, however the
transmission is operating normally.
The transmission uses adaptive
shift controls. Adaptive shift controls
continually compare key shift
parameters to pre-programmed
ideal shifts stored in the
transmission s computer. The
transmission constantly makes
adjustments to improve vehicle
performance according to how the
vehicle is being used, such as with
a heavy load or when the
temperature changes. During this
adaptive shift control process,
shifting might feel different as the
transmission determines the best
settings.
The shift quality of a new vehicle
may not be ideal because the
adaptive shift control process may
not have determined the best
settings for a particular shift or
condition. Shift quality will improve
with continued driving.
When temperatures are very cold,
the transmission's gear shifting
could be delayed, providing more
stable shifts until the engine warms
up. Shifts could be more noticeable
with a cold transmission. This
difference in shifting is normal.