GMC Savana 2016 Owner's Manual page 185

184 Driving and Operating
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.
M : This position lets drivers select
the range of gears appropriate for
current driving conditions. If the
vehicle has this feature, see Range
Selection Mode under Manual
Mode 0 185.
3 : This position is also used for
normal driving. It reduces vehicle
speed more than D (Drive) without
using the brakes. You might choose
3 (Third) instead of D (Drive) when
driving on hilly, winding roads; when
towing a trailer, so there is less
shifting between gears; and when
going down a steep hill. See Range
Selection Mode under Manual
Mode 0 185.
2 : This position reduces vehicle
speed even more than 3 (Third)
without using the brakes. You can
use 2 (Second) on hills. It can help
control vehicle speed as you go
down steep mountain roads, but
then you would also want to use the
brakes off and on. See Range
Selection Mode under Manual
Mode 0 185.
If you manually select 2 (Second) in
an automatic transmission, the
transmission will start in
second gear. You can use this
feature for reducing the speed of the
rear wheels when trying to start the
vehicle from a stop on slippery road
surfaces.
1 : This position reduces vehicle
speed without using the brakes.
You can use it for major/severe
downgrades where the vehicle
would otherwise accelerate due to
steepness of grade. When you shift
to 1 (First) it provides the lowest
gear appropriate to current road
speed and continues to downshift
as the vehicle slows, eventually
downshifting to 1 (First) gear. The
transmission can be held in 1 (First)
gear using Range Selection Mode
or the shift lever. See Range
Selection Mode under Manual
Mode 0 185.