GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Driving and Operating 203
Caution
Pulling a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To pull a trailer
correctly, follow the advice in this
section and see your dealer for
important information about
towing a trailer with the vehicle.
To identify the trailering capacity of
the vehicle, read the information in
“Weight of the Trailer” following.Trailering is different than just
driving the vehicle by itself.
Trailering means changes in
handling, acceleration, braking,
durability, and fuel economy.
Successful, safe trailering takes
correct equipment, and it has to be
used properly.
The following information has many
time-tested, important trailering tips
and safety rules. Many of these are
important for your safety and that of
your passengers. So please read
this section carefully before pulling a
trailer.
Weight of the Trailer
Safe trailering requires monitoring
the weight, speed, altitude, road
grades, outside temperature, the
dimensions of the front of the trailer,
and how frequently the vehicle is
used to pull a trailer are all
important. Take into consideration
any special equipment on the
vehicle, and the amount of tongue
weight the vehicle can carry. See
“Weight of the Trailer Tongue”
later
in this section.
Maximum trailer weight is calculated
assuming only the driver is in the
tow vehicle and it has all the
required trailering equipment. The
weight of additional optional
equipment, passengers, and cargo
in the tow vehicle must be
subtracted from the maximum trailer
weight.
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
232 Vehicle Care
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 be
too 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.
If the overheat warning is displayed
with no sign of steam: 1. Turn the air conditioning 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
outside temperatures, the fan speed
increases as the clutch more fully
engages, so an increase in fan
noise may be heard. This is normal
and should not be mistaken as the
transmission slipping or making
extra shifts. It is merely the cooling
system functioning properly. The fan
will slow down when additional
cooling is not required and the
clutch partially disengages.
This fan noise may be heard when
starting the engine. It will go away
as the fan clutch partially
disengages.
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Vehicle Care 239
2. The use of the vehicle aftersuch device or element of
design has been removed or
rendered inoperative by any
person.
Among those acts presumed to
constitute tampering are the acts
listed below.
Insulation:
Removal of the noise shields or any
underhood insulation.
Engine:
Removal or rendering the engine
speed governor, if equipped,
inoperative so as to allow engine
speed to exceed manufacturer
specifications.
Fan and Drive:
. Removal of the fan clutch,
if equipped, or rendering the
clutch inoperative.
. Removal of the fan shroud,
if equipped. Air Intake:
.
Removal of the air cleaner
silencer.
. Modification of the air cleaner.
Exhaust:
. Removal of the muffler and/or
resonator.
. Removal of the exhaust pipes
and exhaust pipe clamps.
Fuel Operated Heater (FOH) -
Diesel Engine:
. Removal of the muffler.
Starter Switch Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. 2. Apply both the parking brake
and the regular brake.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.
Automatic Transmission
Shift Lock Control
Function Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
248 Vehicle Care
FusesUsage
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 –
13 Interior rear vision camera module
14 Windshield washer Fuses
Usage
16 Horn
17 Transmission
18 A/C
19 Engine control module battery
20 Cutaway/Left stoplamp/Turnlamp
21 Left trailer stoplamp/Turnlamp
22 Cutaway/Right stoplamp/Turnlamp
23 –
24 Fuel pump
25 Auxiliary power outlet
26 Body control module 3
27 Special equipment option Fuses
Usage
28 Airbag
29 Steering wheel sensor
30 Engine control module Ignition
31 Transmission control module
Ignition
32 Transmission control module 1
battery/Engine
control module
battery power (gas
6 cyl)
33 Rear parking aid module
34 –
35 –
36 Fuel system control module battery
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Vehicle Care 249
FusesUsage
41 Transmission control 2 module
battery power
42 Trailer wiring
43 –
44 Starter solenoid
45 Engine control module/Powertrain
46 AC DC inverter
47 Cooling fan –low
51 Left high-beam headlamp
52 Right high-beam headlamp
53 Left low-beam headlamp
54 Right low-beam headlamp Fuses
Usage
55 Wipers
56 Canister vent solenoid
58 Body control module 2
59 Body control module 1
61 Engine oil solenoid
62 O2 sensor 2
63 –
64 Mass air flow/ Canister vent
65 Ignition/Injectors –odd
66 Daytime running lamps 2
67 Daytime running lamps 1 Fuses
Usage
68 Auxiliary stoplamps
69 External power for trailer
70 Upfitter stoplamps
71 Fuel heater/Flex fuel sensor
72 Body control module 6
73 Lighter/Data link connector
74 Front blower
75 V6 fuel injectors
76 –
77 O2 sensor 1
78 Engine control module/Powertrain
79 Ignition/Injectors –even
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
250 Vehicle Care
RelaysUsage
15 Run/Crank
37 –
38 Fuel pump
39 Crank
40 A/C compressor
48 –
49 Powertrain
50 –
57 Cooling fan –low
60 Cooling fan control Auxiliary Fuse Block
This component is near the fuse
block in the engine compartment
Fuses Usage
MR-1 Upfitter 1
MR-2 Upfitter 2
MR-3 Upfitter power control Relays Usage
MR Rel 1 Upfitter 1
MR Rel 2 Upfitter 2
Mega Fuse Holder
Fuse Usage
1 Starter motor
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Vehicle Care 259
Belt:A rubber coated layer of
cords between the plies and the
tread. Cords may be made from
steel or other reinforcing
materials.
Bead
:The tire bead contains
steel wires wrapped by steel
cords that hold the tire onto
the rim.
Bias Ply Tire
:A pneumatic tire
in which the plies are laid at
alternate angles less than
90 degrees to the centerline of
the tread.
Cold Tire Pressure
:The
amount of air pressure in a tire,
measured in kPa (kilopascal)
or psi (pounds per square inch)
before a tire has built up heat
from driving. See Tire Pressure
0 261.
Curb Weight
:The weight of a
motor vehicle with standard and
optional equipment including the maximum capacity of fuel, oil,
and coolant, but without
passengers and cargo.
DOT Markings
:A code molded
into the sidewall of a tire
signifying that the tire is in
compliance with the U.S.
Department of Transportation
(DOT) Motor Vehicle Safety
Standards. The DOT code
includes the Tire Identification
Number (TIN), an alphanumeric
designator which can also
identify the tire manufacturer,
production plant, brand, and
date of production.
GVWR
:Gross Vehicle Weight
Rating. See Vehicle Load Limits
0 167.
GAWR FRT
:Gross Axle Weight
Rating for the front axle. See
Vehicle Load Limits 0167.
GAWR RR
:Gross Axle Weight
Rating for the rear axle. See
Vehicle Load Limits 0167. Intended Outboard Sidewall
:
The side of an asymmetrical tire
that must always face outward
when mounted on a vehicle.
Kilopascal (kPa)
:The metric
unit for air pressure.
Light Truck (LT-Metric) Tire
:A
tire used on light duty trucks and
some multipurpose passenger
vehicles.
Load Index
:An assigned
number ranging from 1 to 279
that corresponds to the load
carrying capacity of a tire.
Maximum Inflation Pressure
:
The maximum air pressure to
which a cold tire can be inflated.
The maximum air pressure is
molded onto the sidewall.
Maximum Load Rating
:The
load rating for a tire at the
maximum permissible inflation
pressure for that tire.