
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
194 Driving and Operating
{Warning
SBZA does not alert the driver to
vehicles rapidly approaching
outside of the side blind zones,
pedestrians, bicyclists,
or animals. It may not provide
alerts when changing lanes under
all driving conditions. Failure to
use proper care when changing
lanes may result in injury, death,
or vehicle damage. Before
making a lane change, always
check mirrors, glance over your
shoulder, and use the turn
signals.SBZA Detection Zones
The SBZA sensor covers a zone of
approximately one lane over from
both sides of the vehicle, or 3.5 m
(11 ft). The height of the zone is
approximately between 0.5 m (1.5 ft)
and 2 m (6 ft) off the ground. This
zone starts at approximately the
middle of the vehicle and goes back
8 m (26 ft).
How the System Works
The SBZA symbol lights up in the
side mirrors when the system
detects a moving vehicle in the next lane over that is in the side blind
zone. This indicates it may be
unsafe to change lanes. Before
making a lane change, check the
SBZA display, check mirrors, glance
over your shoulder, and use the turn
signals.
Left Side Mirror
DisplayRight Side Mirror Display
When the vehicle is started, both
outside mirror SBZA displays will
briefly come on to indicate the
system is operating. When the
vehicle is in a forward gear, the left
or right side mirror display will light
up if a moving vehicle is detected in
that blind zone. If the turn signal is
activated in the same direction of a
detected vehicle, this display will
flash as an extra warning not to
change lanes.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Driving and Operating 195
SBZA can be disabled through the
Driver Information Center (DIC).
SeeDriver Information Center (DIC)
0 109. If SBZA is disabled by the
driver, the SBZA mirror displays will
not light up.
When the System Does Not
Seem to Work Properly
SBZA displays may not come on
when passing a vehicle quickly, for
a stopped vehicle, or when towing a
trailer. The SBZA detection zones
that extend back from the side of
the vehicle do not move further back
when a trailer is towed. Use caution
while changing lanes when towing a
trailer. SBZA may alert to objects
attached to the vehicle, such as a
trailer, bicycle, or object extending
out to either side of the vehicle. This
is normal system operation; the
vehicle does not need service.
SBZA may not always alert the
driver to vehicles in the side blind
zone, especially in wet conditions.
The system does not need to be
serviced. The system may light up
due to guardrails, signs, trees, shrubs, and other non-moving
objects. This is normal system
operation; the vehicle does not need
service.
SBZA may not operate when the
SBZA sensors in the left or right
corners of the rear bumper are
covered with mud, dirt, snow, ice,
or slush, or in heavy rainstorms. For
cleaning instructions, see "Washing
the Vehicle" under
Exterior Care
0 290. If the DIC displays the
system unavailable message after
cleaning both sides of the vehicle
toward the rear corners of the
vehicle, see your dealer.
If the SBZA displays do not light up
when vehicles are in the blind zone
and the system is clean, the system
may need service. Take the vehicle
to your dealer.
Radio Frequency Information
See Radio Frequency Statement
0 326.
Fuel
For diesel engine vehicles, see
“Fuel for Diesel Engines” in the
Duramax diesel supplement.
GM recommends the use of TOP
TIER
®detergent gasoline to keep
the engine cleaner and reduce
engine deposits. See
www.toptiergas.com for a list of TOP
TIER detergent gasoline marketers
and applicable countries.
If the vehicle has a yellow fuel cap
or a yellow sticker on the fuel door,
E85 or FlexFuel can be used. See
E85 or FlexFuel 0197.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
196 Driving and Operating
Use regular unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 87 or
higher. Do not use gasoline with a
posted octane rating of less than 87,
as this may cause engine knock and
will lower fuel economy.
Prohibited Fuels
Caution
Do not use fuels with any of the
following conditions; doing so
may damage the vehicle and void
its warranty:. For vehicles which are not
FlexFuel, fuel labeled
greater than 15% ethanol by
volume, such as mid-level
ethanol blends (16 –50%
ethanol), E85, or FlexFuel.
. Fuel with any amount of
methanol, methylal, and
aniline. These fuels can
corrode metal fuel system
parts or damage plastic and
rubber parts.
(Continued)
Caution (Continued)
.Fuel containing metals such
as methylcyclopentadienyl
manganese tricarbonyl
(MMT), which can damage
the emissions control
system and spark plugs.
. Fuel with a posted octane
rating of less than the
recommended fuel. Using
this fuel will lower fuel
economy and performance,
and may decrease the life of
the emissions catalyst.
California Fuel
Requirements
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. See
the underhood emission control
label. If this fuel is not available in
states adopting California Emissions
Standards, the vehicle will operate
satisfactorily on fuels meeting federal specifications, but emission
control system performance may be
affected. The malfunction indicator
lamp could turn on and the vehicle
may not pass a smog-check test.
See
Malfunction Indicator Lamp
(Check Engine Light) 0103. If this
occurs, return to your authorized
dealer for diagnosis. If it is
determined that the condition is
caused by the type of fuel used,
repairs may not be covered by the
vehicle warranty.
Fuels in Foreign
Countries
The U.S., Canada, and Mexico post
fuel octane ratings in anti-knock
index (AKI). For fuel not to use in a
foreign country, see “Prohibited
Fuels” inFuel 0195.
Fuel Additives
To keep fuel systems clean, TOP
TIER detergent gasoline is
recommended. See Fuel0195.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Driving and Operating 199
When replacing the fuel cap, turn it
clockwise until it clicks. Make sure
the cap is fully installed. The
diagnostic system can determine if
the fuel cap has been left off or
improperly installed. This would
allow fuel to evaporate into the
atmosphere. SeeMalfunction
Indicator Lamp (Check Engine
Light) 0103.
{Warning
If a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel by
shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
Caution
If a new fuel cap is needed, be
sure to get the right type of cap
from your dealer. The wrong type
of fuel cap may not fit properly,
(Continued)
Caution (Continued)
may cause the malfunction
indicator lamp to light, and could
damage the fuel tank and
emissions system. See
Malfunction Indicator Lamp
(Check Engine Light)0103.
Filling a Portable Fuel
Container
{Warning
Filling a portable fuel container
while it is in the vehicle can cause
fuel vapors that can ignite either
by static electricity or other
means. You or others could be
badly burned and the vehicle
could be damaged. Always:
. Use approved fuel
containers.
(Continued)
Warning (Continued)
.Remove the container from
the vehicle, trunk, or pickup
bed before filling.
. Place the container on the
ground.
. Place the nozzle inside the
fill opening of the container
before dispensing fuel, and
keep it in contact with the fill
opening until filling is
complete.
. Fill the container no more
than 95% full to allow for
expansion.
. Do not smoke, light
matches, or use lighters
while pumping fuel.
. Avoid using cell phones or
other electronic devices.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
208 Driving and Operating
State and local regulations may also
require the trailer to have its own
braking system if loaded above a
certain threshold. These
requirements vary from state to
state.
Be sure to read and follow the
instructions for the trailer brakes so
they are installed, adjusted, and
maintained properly.
Do not tap into the vehicle's
hydraulic brake system.
Trailer Wiring Harness
The optional heavy-duty trailer
wiring package includes a wiring
harness, with a seven-pin connector
at the rear of the vehicle and a
four-wire harness assembly under
the driver side of the instrument
panel. The four-wire harness
assembly comes without a
connector.
If the vehicle does not have a trailer
hitch, the seven-wire harness
assembly with connector is taped
together and located in a frame
pocket at the driver side rear left
corner of the frame.If the vehicle has a trailer hitch, the
seven-wire harness assembly with
connector is attached to a bracket
on the hitch platform. In both cases,
the seven-wire harness has a
connector and includes a 30-amp
feed wire.
Use only a round, seven-wire
connector with flat blade terminals
meeting SAE J2863 specifications
for proper electrical connectivity.
The seven-wire harness connector
contains the following trailer circuits:
.
Light Green: Back-up Lamps
(10A fuse)**
. White: Ground
. Dark Blue: Trailer Brake Signal
. Dark Green: Right Rear Stop
and Turn Signal*
. Red/Black Stripe: Battery Feed
(30A Fuse)
. Brown: Trailer Park Lamp
Supply Voltage (15A fuse)**
. Yellow: Left Rear Stop and Turn
Signal * The four-wire harness (without
connector) contains the following
circuits:
.
Black: Ground
. Red/White: Battery Feed
. Dark Blue: Trailer Brake Signal
. Light Blue: CHMSL/Stoplamp
Supply Voltage
* If the vehicle is a cutaway with
trailer provisions, a 15 amp fuse will
be shared for both left/stop trailer
turn and right/stop trailer turn
signals. However, the cutaway
lighting connector will have a
10 amp fuse for each signal.
** If the vehicle is a cutaway with
trailer provisions, a 15 amp fuse will
be shared for trailer park lamps and
cutaway rear lighting connector park
lamps. Also, a 10 amp fuse will be
shared for trailer back-up lamps and
cutaway rear lighting connector
back-up lamps.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Driving and Operating 209
Tow/Haul Mode
This button is on the instrument
panel, to the right of the steering
wheel.
Pressing this button turns on and off
the Tow/Haul Mode.
This indicator light on the instrument
cluster comes on when the Tow/
Haul Mode is on.
Tow/Haul is a feature that assists
when pulling a heavy trailer or a
large or heavy load. SeeTow/Haul
Mode 0184.
Tow/Haul is designed to be most
effective when the vehicle and
trailer combined weight is at least
75 percent of the vehicle Gross
Combined Weight Rating (GCWR). See
“Weight of the Trailer” inTrailer
Towing 0202. Tow/Haul is most
useful under the following driving
conditions:
. When pulling a heavy trailer or a
large or heavy load through
rolling terrain.
. When pulling a heavy trailer or a
large or heavy load in
stop-and-go traffic.
. When pulling a heavy trailer or a
large or heavy load in busy
parking lots where improved low
speed control of the vehicle is
desired.
Operating the vehicle in Tow/Haul
Mode when lightly loaded or with no
trailer at all will not cause damage.
However, there is no benefit to the
selection of Tow/Haul when the
vehicle is unloaded. Such a
selection when unloaded may result
in unpleasant engine and
transmission driving characteristics
and reduced fuel economy. Tow/
Haul is recommended only when
pulling a heavy trailer or a large or
heavy load.
Trailer Sway
Control (TSC)
Trailer sway is unintended
side-to-side motion of a trailer while
being towed. If the vehicle is towing
a trailer and the TSC detects that
sway is increasing, the vehicle
brakes are selectively applied at
each wheel, to help reduce
excessive trailer sway.
When TSC is active, the Traction
Control System (TCS)/StabiliTrak
warning light will flash on the
instrument cluster. Vehicle speed
must be reduced. If trailer sway
continues, StabiliTrak can reduce
engine torque to help slow the
vehicle. See Traction Control/
Electronic Stability Control 0186.
{Warning
Even if the vehicle is equipped
with TSC, trailer sway could result
in loss of control and the vehicle
could crash. If excessive trailer
sway is detected, slow down to a
(Continued)

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
210 Driving and Operating
Warning (Continued)
safe speed. Check the trailer and
vehicle to help correct possible
causes. These could include an
improperly or overloaded trailer,
unrestrained cargo, improper
trailer hitch configuration,
excessive vehicle-trailer speed,
or improperly inflated or incorrect
vehicle or trailer tires. SeeTowing
Equipment 0207 for trailer ratings
and hitch setup
recommendations.
Adding non-dealer accessories can
affect the vehicle performance. See
Accessories and Modifications
0 213.
Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service
and Emission Inspection/
Maintenance testing. See
Malfunction Indicator Lamp
(Check Engine Light) 0103.
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle’s
systems.
Caution
Some electrical equipment can
damage the vehicle or cause
components to not work and
would not be covered by the
vehicle warranty. Always check
with your dealer before adding
electrical equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle 066 and Adding Equipment
to the Airbag-Equipped Vehicle
0 66.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
222 Vehicle Care
suspected, use the following
procedures to check the fluid level.
However, if there is a large leak, it
may be necessary to have the
vehicle towed to a dealer and have
it repaired before driving the vehicle
further.
Change the fluid and filter at the
intervals listed inMaintenance
Schedule 0301, and be sure to use
the transmission fluid listed in
Recommended Fluids and
Lubricants 0308.
How to Check Automatic
Transmission Fluid
Because this operation can be
difficult, it is recommended to have
this check done at your dealer,
which can monitor the transmission
temperature. The transmission fluid
level increases with temperature. To
obtain a highly accurate fluid level
check, the transmission temperature
must be measured.
If it is decided to check the fluid
level, be sure to follow all the
instructions here, or a false reading
on the dipstick may occur.
Caution
Too much or too little fluid can
damage the transmission. Too
much can mean that some of the
fluid could come out and fall on
hot engine parts or exhaust
system parts, starting a fire. Too
little fluid could cause the
transmission to overheat. Be sure
to get an accurate reading if
checking the transmission fluid.
Wait at least 30 minutes with the
engine off, before checking the
transmission fluid level if the vehicle
has been driven:
. In hot weather, when outside
temperatures are above 32 °C
(90 °F).
. The vehicle is heavily loaded.
. At high speed for quite a while in
hot weather.
. In heavy traffic and hot weather.
. While pulling a trailer. After driving under these conditions,
a hot check can be performed. The
fluid should be hot, which is 71 °C to
93 °C (160 °F to 200 °F).
A cold fluid level check can be
performed after the vehicle has
been sitting for eight hours or more
with the engine off, but this is used
only as a reference. Let the engine
run at idle for five minutes if the
outside temperature is between
15 °C to 32 °C (60 °F to 90 °F).
Should the fluid level be low during
this cold check, the fluid must be
checked warm or hot before adding
fluid. If the outside temperature is
colder than 15 °C (60 °F) or hotter
than 32 °C (90 °F), a cold check
cannot be performed.
A warm fluid level check can be
performed by driving the vehicle
under lightly loaded conditions and
outside temperatures between 10 °C
to 27 °C (50 °F to 80 °F). The
vehicle should be driven for at least
24 km (15 mi) before performing a
warm check. Checking the fluid