
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-9967828) -
2017 - crc - 5/6/16
Driving and Operating 211
the driver door, or seeVehicle Load
Limits 0172. Make sure not to go
over the GVW limit for the vehicle,
or the GAWR, including the weight
of the trailer tongue. If using a
weight distributing hitch, make sure
not to go over the rear axle limit
before applying the weight
distribution spring bars.
Towing Equipment
Hitches
The correct hitch equipment helps
maintain combination control. Many
trailers can be towed with a
weight-carrying hitch which simply
features a coupler latched to the
hitch ball, or a tow eye latched to a
pintle hook. Other trailers may
require a weight-distributing hitch
that uses spring bars to distribute
the trailer tongue weight among the
two vehicle and trailer axles. See
“Weight of the Trailer Tongue” under
Trailer Towing 0206 for rating limits
with various hitch types. Consider using sway controls with
any trailer. Ask a trailering
professional about sway controls or
refer to the trailer manufacturer's
recommendations and instructions.
Weight-Distributing Hitches
and Weight Carrying Hitches
A weight distributing hitch may be
useful with some trailers. Use the
following guidelines to determine if a
weight distributing hitch should
be used.
1. Front of Vehicle
2. Body to Ground Distance
When using a weight-distributing
hitch, the hitch must be adjusted so
the distance (2) remains the same
both before and after coupling the
trailer to the tow vehicle.
Safety Chains
Always attach chains between the
vehicle and the trailer. Cross the
safety chains under the tongue of
the trailer to help prevent the tongue
from contacting the road if it
becomes separated from the hitch.
Always leave just enough slack so
the rig can turn. Never allow safety
chains to drag on the ground.
Trailer Brakes
A loaded trailer that weighs more
than 680 kg (1,500 lb) must be
equipped with its own brake system,
with brakes working on all axles.
Trailer braking equipment
conforming to Canadian Standards
Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-9967828) -
2017 - crc - 5/6/16
212 Driving and Operating
State and local regulations may also
require the trailer to have its own
braking system if loaded above a
certain threshold.
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.
Tow/Haul Mode
This button is on the instrument
panel, to the right of the steering
wheel.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-9967828) -
2017 - crc - 5/6/16
Driving and Operating 213
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 0188.
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 0206. 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.
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)
0 102. 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.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-9967828) -
2017 - crc - 5/2/16
224 Vehicle Care
Caution (Continued)
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
warm or hot will give a more
accurate reading of the fluid level
than a cold check.
Because the vehicle is equipped
with a high-efficiency air-to-oil
cooler, the transmission fluid
temperature may not reach therequired hot fluid level checking
temperature under normal lightly
loaded driving vehicle conditions.
Checking the Fluid Level
Prepare the vehicle:
1. Park the vehicle on a level place. Keep the engine
running.
2. With the parking brake applied, place the shift lever in P (Park).
3. With a foot on the brake pedal, move the shift lever through
each gear range, pausing for
about three seconds in each
range. When M is reached,
move the selector from M1
through M3. Then, position the
shift lever in P (Park).
4. Let the engine run at idle for two minutes or more.
Then, without shutting off the
engine, use the steps that follow.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-9967828) -
2017 - crc - 5/2/16
232 Vehicle Care
If Steam is Coming from the
Engine Compartment
{Warning
Steam from an overheated engine
can burn you badly, even if you
just open the hood. Stay away
from the engine if you see or hear
steam coming from it. Just turn it
off and get everyone away from
the vehicle until it cools down.
Wait until there is no sign of
steam or coolant before you open
the hood.
If you keep driving when the
engine is overheated, the liquids
in it can catch fire. You or others
could be badly burned. Stop the
engine if it overheats, and get out
of the vehicle until the engine
is cool.
If No Steam is Coming from
the Engine Compartment
If an engine overheat warning is
displayed but no steam can be seen
or heard, the problem may not betoo serious. Sometimes the engine
can get a little too hot when the
vehicle:
.
Climbs a long hill on a hot day.
. Stops after high-speed driving.
. Idles for long periods in traffic.
. Tows a trailer. See “Driving on
Grades” underTrailer
Towing 0206.
If the overheat warning is displayed
with no sign of steam: 1. Turn the air off.
2. Turn the heater on to the highest temperature and to the
highest fan speed. Open the
windows as necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or
N (Neutral) and let the
engine idle.
If the engine coolant temperature
gauge is no longer in the overheat
zone or an overheat warning no
longer displays, the vehicle can be
driven. Continue to drive the vehicle
slowly for about 10 minutes. Keep a
safe vehicle distance from the vehicle in front. If the warning does
not come back on, continue to drive
normally and have the cooling
system checked for proper fill and
function.
If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is still no sign of steam,
push down the accelerator until the
engine speed is about twice as fast
as normal idle speed for at least
three minutes while parked. If the
warning is still on, turn off the
engine until it cools down.
If the decision is made not to lift the
hood, get service help right away.
Engine Fan
The vehicle has a clutched engine
cooling fan. When the clutch is
engaged, the fan spins faster to
provide more air to cool the engine.
In most everyday driving conditions,
the fan is spinning slower and the
clutch is not fully engaged. This
improves fuel economy and reduces
fan noise. Under heavy vehicle
loading, trailer towing, and/or high

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-9967828) -
2017 - crc - 5/2/16
248 Vehicle Care
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.Fuses Usage
1 ABS motor
2 ABS module Fuses Usage
3 Right trailer stoplamp/Turnlamp
4 –
5 –
6 Fuel system control module/Ignition
7 Body control module 5
8 Body control module 7
9 Body control module 4
10 Instrument cluster
11 Trailer wiring
12 Interior rear vision camera module
13 –
14 Windshield washer
16 Horn
17 Transmission
18 A/C

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-9967828) -
2017 - crc - 5/2/16
Vehicle Care 249
FusesUsage
19 Engine control module battery
20 –
21 Left trailer stoplamp/Turnlamp
22 –
23 –
24 Fuel pump
25 Auxiliary power outlet
26 Body control module 3
27 Special equipment option
28 Airbag
29 Steering wheel sensor
30 Engine control module/Ignition/
Glow plug module
31 Transmission control module/
Ignition Fuses
Usage
32 Transmission control module
battery
33 Rear parking aid module
34 –
35 Fuel operated heater module
36 Fuel system control module battery
41 –
42 Trailer wiring
43 EV fan clutch
44 Starter solenoid
45 Engine control module/Powertrain
46 –
47 Cooling fan –low
51 Left high-beam headlamp
52 Right high-beam headlamp Fuses
Usage
53 Left low-beam headlamp
54 Right low-beam headlamp
55 Wipers
56 Canister vent solenoid
58 Body control module 2
59 Body control module 1
61 –
62 O2 sensor 2/EV fan (diesel)
63 –
64 Mass air flow/ Canister vent
65 Ignition/Injectors –odd
66 Daytime running lamps 2
(LOLVL-V22) (if
equipped)

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-9967828) -
2017 - crc - 5/2/16
250 Vehicle Care
FusesUsage
67 Daytime running lamps 1 (UPLVL
+V22) (if equipped)
68 Auxiliary stoplamps
69 Trailer stoplamps
70 –
71 Fuel heater/Flex fuel sensor
72 Body control module 6
73 Lighter/Data link connector
74 Front blower
75 Fuel injectors
76 –
77 O2 sensor 2
78 Engine control module/Powertrain
79 Ignition/Injectors –even Relays
Usage
15 Run/Crank
37 –
38 Fuel pump
39 Crank
40 A/C
48 EV fan clutch
49 Powertrain
50 –
57 Cooling fan –low
60 Fan controlFloor Console Fuse Block
The floor console fuse block is
under the driver seat.