trailer GMC SAVANA 2015 Owner's Guide

Black plate (47,1)GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-7707482) -
2015 - crc - 1/20/15
Driving and Operating 9-47
Maintenance when Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See
Maintenance Schedule on
page 11-3. Things that are
especially important in trailer
operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system, and
brake system. It is a good idea to
inspect these before and during
the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Trailer Towing
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
{Warning
The driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly. For
example, if the trailer is too
heavy, the brakes may not work
well—or even at all. The driver
and passengers could be
seriously injured. The vehicle may
also be damaged; the resulting
repairs would not be covered by
the vehicle warranty. Pull a trailer
only if all the steps in this section
have been followed. Ask your
dealer for advice and information
about towing a trailer with the
vehicle.
{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.

Black plate (48,1)GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-7707482) -
2015 - crc - 1/20/15
9-48 Driving and Operating
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
How heavy can a trailer safely be?
It depends on how the rig is used.
For example, speed, altitude, road
grades, outside temperature, and
how much the vehicle is used to pull
a trailer are all important. It can
depend on 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.
Use the following chart to determine
how much the vehicle can weigh,
based upon the vehicle model and
options.

Black plate (49,1)GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-7707482) -
2015 - crc - 1/20/15
Driving and Operating 9-49
VehicleAxle Ratio Maximum Trailer Weight GCWR*
G2500 Cargo Van 2WD Short Wheelbase 4.8L V8 3.423 357 kg (7,400 lb) 5 897 kg (13,000 lb)
6.0L V8 3.424 536 kg (10,000 lb) 7 257 kg (16,000 lb)
G2500 Cargo Van 2WD Long Wheelbase 4.8L V8 3.423 266 kg (7,200 lb) 5 897 kg (13,000 lb)
6.0L V8 3.424 536 kg (10,000 lb) 7 257 kg (16,000 lb)
G2500 Passenger Van 2WD Short Wheelbase 4.8L V8 3.423 039 kg (6,700 lb) 5 897 kg (13,000 lb)
6.0L V8 3.424 445 kg (9,800 lb) 7 257 kg (16,000 lb)
G3500 Cargo Van 2WD Short Wheelbase 4.8L V8 3.423 357 kg (7,400 lb) 5 897 kg (13,000 lb)
6.0L V8 3.424 536 kg (10,000 lb) 7 257 kg (16,000 lb)
G3500 Cargo Van 2WD Long Wheelbase
4.8L V8 3.423 221 kg (7,100 lb) 5 897 kg (13,000 lb)
6.0L V8 3.424 536 kg (10,000 lb) 7 257 kg (16,000 lb)
G3500 Passenger Van 2WD Short Wheelbase
6.0L V8 3.424 400 kg (9,700 lb) 7 257 kg (16,000 lb)

Black plate (50,1)GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-7707482) -
2015 - crc - 1/20/15
9-50 Driving and Operating
VehicleAxle Ratio Maximum Trailer Weight GCWR*
G3500 Passenger Van 2WD Long Wheelbase 6.0L V8 3.424 218 kg (9,300 lb) 7 257 kg (16,000 lb)
*The Gross Combined Weight Rating (GCWR) is the total allowable weight of the completely loaded vehicle and
trailer including any passengers, cargo, equipment, and conversion. The GCWR for the vehicle should not be
exceeded.
Ask your dealer for trailering
information or advice.
Weight of the Trailer Tongue
The tongue load (1) of any trailer is
an important weight to measure
because it affects the total gross
weight of the vehicle. The Gross
Vehicle Weight (GVW) includes the
curb weight of the vehicle, any
cargo carried in it, and the people
who will be riding in the vehicle.
If there are a lot of options,
equipment, passengers, or cargo in
the vehicle, it will reduce the tongue
weight the vehicle can carry, which
will also reduce the trailer weight the
vehicle can tow. If towing a trailer, the tongue load must be added to
the GVW because the vehicle will
be carrying that weight, too. See
Vehicle Load Limits on page 9-9
for
more information about the vehicle's
maximum load capacity.
The trailer tongue weight (1) should
be 10 percent to 15 percent of the
total loaded trailer weight (2), up to a
maximum of 181 kg (400 lb) with a
weight carrying hitch. The trailer
tongue weight (1) should be

Black plate (51,1)GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-7707482) -
2015 - crc - 1/20/15
Driving and Operating 9-51
10 percent to 15 percent of the total
loaded trailer weight (2), up to a
maximum of 454 kg (1,000 lb) with a
weight distributing hitch.
Do not exceed the maximum
allowable tongue weight for the
vehicle. Choose the shortest hitch
extension that will position the hitch
ball closest to the vehicle. This will
help reduce the effect of trailer
tongue weight on the rear axle.
After loading the trailer, weigh the
trailer and then the tongue,
separately, to see if the weights are
proper. If they are not, adjustments
might be made by moving some
items around in the trailer.
Trailering may be limited by the
vehicle's ability to carry tongue
weight. Tongue weight cannot cause
the vehicle to exceed the GVWR
(Gross Vehicle Weight Rating) or
the RGAWR (Rear Gross Axle
Weight Rating). The effect of
additional weight may reduce the
trailering capacity more than the
total of the additional weight.It is important that the vehicle does
not exceed any of its ratings
—
GCWR, GVWR, RGAWR, Maximum
Trailer Rating, or Tongue Weight.
The only way to be sure it is not
exceeding any of these ratings is to
weigh the vehicle and trailer.
Total Weight on the Vehicle's
Tires
Be sure the vehicle tires are inflated
to the upper limit for cold tires.
These numbers can be found on the
Certification label at the rear edge of
the driver door, or see Vehicle Load
Limits on page 9-9. 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 on page 9-47 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.

Black plate (52,1)GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-7707482) -
2015 - crc - 1/20/15
9-52 Driving and Operating
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. Body to Ground Distance
2. Front of Vehicle
When using a weight-distributing
hitch, the hitch must be adjusted so
the distance (1) 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) needs to have
its own brake system that is
adequate for the weight of the
trailer. Be sure to read and follow
the instructions for the trailer brakes
so they are installed, adjusted and
maintained properly.
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 instrumentpanel. 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.
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*

Black plate (53,1)GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-7707482) -
2015 - crc - 1/20/15
Driving and Operating 9-53
.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.
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. See
Tow/Haul
Mode on page 9-27. 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 on page 9-47. 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

Black plate (54,1)GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-7707482) -
2015 - crc - 1/20/15
9-54 Driving and Operating
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
{Caution
Some electrical equipment can
damage the vehicle or cause
components to not work and
would not be covered by the
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 on page 3-26
andAdding
Equipment to the Airbag-Equipped
Vehicle on page 3-26.

Black plate (11,1)GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-7707482) -
2015 - crc - 1/20/15
Vehicle Care 10-11
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(Continued)
Caution (Continued)
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.

Black plate (20,1)GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-7707482) -
2015 - crc - 1/20/15
10-20 Vehicle Care
{Caution
Running the engine without
coolant may cause damage or a
fire. Vehicle damage would not be
covered by the vehicle warranty.
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.(Continued)
Warning (Continued)
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 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. See“Driving on
Grades” underTrailer Towing on
page 9-47. 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 fit and
function.
If the warning continues, pull over,
stop, and park the vehicle
right away.