GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Driving and Operating 201
Trailering Weight Ratings
When towing a trailer, the combined
weight of the vehicle, vehicle
contents, trailer, and trailer contents
must be below all of the maximum
weight ratings for the vehicle,
including:
.GCWR: Gross Combined Weight
Rating
. GVWR: Gross Vehicle Weight
Rating
. Maximum Trailer Weight Rating
. GAWR-RR: Gross Axle Weight
Rating-Rear
. Maximum Trailer Tongue Weight
Rating
See “Weight-Distributing Hitch
Adjustment” underTowing
Equipment 0207 to determine if
equalizer bars are required to obtain
the maximum trailer weight rating. See
“Trailer Brakes” underTowing
Equipment 0207 to determine if
brakes are required based on your
trailer's weight.
The only way to be sure the weight
is not exceeding any of these
ratings is to weigh the tow vehicle
and trailer combination, fully loaded
for the trip, getting individual
weights for each of these items.
{Warning
You and others could be seriously
injured or killed if the trailer is too
heavy or the trailer brakes are
inadequate for the load. The
vehicle may be damaged, and the
repairs would not be covered by
the vehicle warranty.
Only tow a trailer if all the steps in
this section have been followed.
Ask your dealer for advice and
information about towing a trailer.
Gross Combined Weight
Rating (GCWR)
GCWR is the total allowable weight
of the completely loaded vehicle
and trailer including any fuel,
passengers, cargo, equipment, and
accessories. Do not exceed the
GCWR for your vehicle. The GCWR
for the vehicle is on the Tow Rating
Chart following.
To check that the weight of the
vehicle and trailer are within the
GCWR for the vehicle, follow these
steps:
1. Start with the curb weight from the Tow Rating Chart.
2. Add the weight of the trailer loaded with cargo and ready
for the trip.
3. Add the weight of all passengers.
4. Add the weight of all cargo in the vehicle.
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
208 Driving and Operating
Weight-Distributing Hitch
Adjustment
A weight distributing hitch may be
useful with some trailers.
1. Front of Vehicle
2. Body to Ground Distance
When using a weight-distributing
hitch, measure the front fender
height distance (2) before
connecting the trailer. Adjust the
spring bars until the front fender
height distance (2) is the same
height before the trailer wasconnected. Do not reduce the front
fender height below the initial
distance (2).
Tires
.
Do not tow a trailer while using a
compact spare tire on the
vehicle.
. Tires must be properly inflated to
support loads while towing a
trailer. See Tires0254 for
instructions on proper tire
inflation.
Safety Chains
Always attach chains between the
vehicle and the trailer, and attach
the chains to the holes on the trailer
hitch platform. Instructions about
safety chains may be provided by
the hitch manufacturer or by the
trailer manufacturer.
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 combination can turn.
Never allow safety chains to drag on
the ground.
Trailer Brakes
Loaded trailers over 675 kg
(1,500 lb) must be equipped with
brake systems and with brakes for
each axle. Trailer braking equipment
conforming to Canadian Standards
Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State or local regulations may
require trailers to have their own
braking system if the loaded weight
of the trailer exceeds certain
minimums that can vary from state
to state. Read and follow the
instructions for the trailer brakes so
they are installed, adjusted, and
maintained properly. Never attempt
to tap into your vehicle's hydraulic
brake system. If you do, both the
vehicle anti-lock brakes and the
trailer brakes may not function,
which could result in a crash.
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Driving and Operating 209
Trailer Wiring Harness
Basic Trailer Wiring
If the vehicle is not equipped with a
trailer connector on the rear bumper,
a seven-wire trailering harness is
tied to the vehicle’s frame. The
harness requires the installation of a
trailer connector, which is available
through your dealer.
Use only a round, seven-wire
connector with flat blade terminals
meeting SAE J2863 specifications
for proper electrical connectivity.
The seven-wire harness contains
the following trailer circuits:Stop/Turn
Signal Left* Yellow
Stop/Turn
Signal Right* Dark Green
Tail/Parking
Lamps** Brown
Reverse
Lamps** Light Green
Battery Feed Red/Black
Ground White Electric Trailer
Brake
Dark Blue
*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.
Heavy-Duty Trailer Wiring Harness
Package
lf equipped, the trailer wiring
harness, with a seven-pin connector
is mounted on the trailer hitch.
1. Left Turn/Brake
2. Taillamps
3. Reverse Lamps
4. Battery Feed
5. Right Turn/Brake
6. Electric Brakes
7. Ground
Electric Brake Control Wiring
Provisions
If the vehicle is not equipped with
an integrated trailer brake controller,
and the trailer has electric brakes, a
trailer brake controller needs to be
installed on the vehicle. The brake
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
210 Driving and Operating
controller should be installed by
your dealer or a qualified service
center.
If equipped, wiring provisions for an
aftermarket electric trailer brake
controller are included with the
vehicle as part of the trailer wiring
package. The harness contains the
following circuits:Electric Trailer
Brakes Dark Blue
Battery Feed Red/White
Brake Apply
Signal Light Blue
Ground Black
There are four blunt cut wires under
the floor carpeting in front of the
brake pedal. It will be necessary to
have a technician connect the
12-volt power to the engine
compartment fuse block.
Refer to the aftermarket electric
trailer brake controller owner's
manual to determine wire color
coding of the electric trailer brake controller. The wire colors on the
brake controller may be different
from the vehicle.
Trailer Lamps
Always check all trailer lamps are
working at the beginning of each
trip, and periodically on longer trips.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals will illuminate to indicate
the vehicle is turning, changing
lanes, or stopping. When towing a
trailer, the arrows on the instrument
cluster will illuminate even if the
trailer is not properly connected or
the bulbs are burned out.
Tow/Haul Mode
Tow/Haul assists when pulling a
heavy trailer or a large or heavy
load. For instructions on how to
enter Tow/Haul mode, see
Tow/Haul
Mode 0174.
Tow/Haul Mode is designed to be
most effective when the vehicle and
trailer combined weight is at least 75% of the vehicle's Gross
Combined Weight Rating (GCWR).
See
“Trailer Weight ”under Trailer
Towing 0200.
Tow/Haul Mode is most useful when
towing a heavy trailer or carrying a
large or heavy load:
. through rolling terrain
. in stop-and-go traffic
. in busy parking lots
Operating the vehicle in Tow/Haul
Mode when lightly loaded or not
towing will not cause damage;
however, it is not recommended and
may result in unpleasant engine and
transmission driving characteristics
and reduced fuel economy.
Trailer Sway
Control (TSC)
Vehicles with StabiliTrak/Electronic
Stability Control (ESC) have a
Trailer Sway Control (TSC) feature.
Trailer sway is unintended
side-to-side motion of a trailer while
towing. If the vehicle is towing a
trailer and the TSC detects that
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Driving and Operating 211
sway is increasing, the vehicle
brakes are selectively applied at
each wheel, to help reduce
excessive trailer sway. If equipped
with the Integrated Trailer Brake
Control (ITBC) system, and the
trailer has an electric brake system,
StabiliTrak/ESC may also apply the
trailer brakes.
If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak/
ESC warning light will flash on the
instrument cluster. Reduce vehicle
speed by gradually removing your
foot from the accelerator. If trailer
sway continues, StabiliTrak/ESC
can reduce engine torque to help
slow the vehicle. TSC will not
function if StabiliTrak/ESC is turned
off. SeeTraction Control/Electronic
Stability Control 0177.
{Warning
Trailer sway can result in a crash
and in serious injury or death,
even if the vehicle is equipped
with TSC.
If the trailer begins to sway,
reduce vehicle speed by
gradually removing your foot from
the accelerator. Then pull over to
check the trailer and vehicle to
help correct possible causes,
including an improperly or
overloaded trailer, unrestrained
cargo, improper trailer hitch
configuration, or improperly
inflated or incorrect vehicle or
trailer tires. See Towing
Equipment 0207 for trailer ratings
and hitch setup
recommendations.
Trailer Tires
Special Trailer (ST) tires differ from
vehicle tires. Trailer tires are
designed with stiff sidewalls to help
prevent sway and to support heavy
loads. These features can make it
difficult to determine if the trailer tire
pressures are low only based on a
visual inspection.
Always check all trailer tire
pressures before each trip when the
tires are cool. Low trailer tire
pressure is a leading cause of trailer
tire blow-outs.
Trailer tires deteriorate over time.
The trailer tire sidewall will show the
week and year the tire was
manufactured. Many trailer tire
manufacturers recommend
replacing tires more than six
years old.
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Vehicle Care 213
Vehicle Care
General Information
General Information . . . . . . . . . . 214
California Proposition65 Warning . . . . . . . . . . . . . . . . . 214
California Perchlorate Materials Requirements . . . . . 215
Accessories and Modifications . . . . . . . . . . . . . . . . 215
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 215
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 216
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 217
Engine Oil . . . . . . . . . . . . . . . . . . . . 221
Engine Oil Life System . . . . . . . 223
Automatic Transmission Fluid (6-Speed Transmission) . . . . . 224
Automatic Transmission Fluid (8-Speed Transmission) . . . . . 227
Engine Air Cleaner/Filter . . . . . . 228
Cooling System . . . . . . . . . . . . . . 229
Engine Overheating . . . . . . . . . . 234
Engine Fan . . . . . . . . . . . . . . . . . . . 235
Power Steering Fluid . . . . . . . . . 235
Washer Fluid . . . . . . . . . . . . . . . . . 236 Brakes . . . . . . . . . . . . . . . . . . . . . . . 237
Brake Fluid . . . . . . . . . . . . . . . . . . . 238
Battery - North America . . . . . . 239
Rear Axle . . . . . . . . . . . . . . . . . . . . 240
Noise Control System . . . . . . . . 240
Starter Switch Check . . . . . . . . . 241
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 242
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 242
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 242
Wiper Blade Replacement . . . . 243
Windshield Replacement . . . . . 243
Headlamp Aiming
Front Headlamp Aiming . . . . . . 244
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 244
Halogen Bulbs . . . . . . . . . . . . . . . . 244
Front Turn Signal, Sidemarker, and Parking Lamps . . . . . . . . . 244
Taillamps . . . . . . . . . . . . . . . . . . . . . 245
Center High-Mounted Stoplamp (CHMSL) . . . . . . . . . 246
License Plate Lamp . . . . . . . . . . 247
Electrical System
Electrical System Overload . . . 247 Fuses and Circuit Breakers . . . 248
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 248
Floor Console Fuse Block . . . . 252
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 254
All-Season Tires . . . . . . . . . . . . . . 255
Winter Tires . . . . . . . . . . . . . . . . . . 255
Tire Sidewall Labeling . . . . . . . . 256
Tire Designations . . . . . . . . . . . . . 258
Tire Terminology and Definitions . . . . . . . . . . . . . . . . . . 259
Tire Pressure . . . . . . . . . . . . . . . . . 262
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 263
Tire Pressure Monitor
Operation . . . . . . . . . . . . . . . . . . . 264
Tire Inspection . . . . . . . . . . . . . . . . 267
Tire Rotation . . . . . . . . . . . . . . . . . 267
Dual Tire Rotation . . . . . . . . . . . . 269
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 269
Buying New Tires . . . . . . . . . . . . . 270
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 271
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 272
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 273
Wheel Replacement . . . . . . . . . . 273
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Vehicle Care 215
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, seat belt pretensioners,
and lithium batteries contained in
electronic keys, may contain
perchlorate materials. Perchlorate
Material–special handling may
apply. See www.dtsc.ca.gov/
hazardouswaste/perchlorate.
Accessories and
Modifications
Adding non-dealer accessories or
making modifications to the vehicle
can affect vehicle performance and
safety, including such things as
airbags, braking, stability, ride and
handling, emissions systems,
aerodynamics, durability, and
electronic systems like antilock
brakes, traction control, and stability
control. These accessories or
modifications could even cause
malfunction or damage not covered
by the vehicle warranty. Damage to suspension components
caused by modifying vehicle height
outside of factory settings will not be
covered by the vehicle warranty.
Damage to vehicle components
resulting from modifications or the
installation or use of non-GM
certified parts, including control
module or software modifications, is
not covered under the terms of the
vehicle warranty and may affect
remaining warranty coverage for
affected parts.
GM Accessories are designed to
complement and function with other
systems on the vehicle. See your
dealer to accessorize the vehicle
using genuine GM Accessories
installed by a dealer technician.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle 054.
Vehicle Checks
Doing Your Own
Service Work
{Warning
It can be dangerous to work on
your vehicle if you do not have
the proper knowledge, service
manual, tools, or parts. Always
follow owner ’s manual procedures
and consult the service manual
for your vehicle before doing any
service work.
If doing some of your own service
work, use the proper service
manual. It tells you much more
about how to service the vehicle
than this manual can. To order the
proper service manual, see
Publication Ordering Information
0 329.
GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Vehicle Care 219
1.Battery - North America 0239.
2. Radiator Pressure Cap. See Cooling System 0229.
3. Coolant Recovery Tank. See Cooling System 0229.
4. Engine Cooling Fan (Out of View). See Cooling System
0 229.
5. Engine Air Cleaner/Filter 0228.
6. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil 0221.
7. Engine Oil Fill Cap. See “When
to Add Engine Oil” under
Engine Oil 0221. 8. Power Steering Fluid
Reservoir. See Power Steering
Fluid 0235.
9. Engine Compartment Fuse
Block 0248.
10. Brake Master Cylinder Reservoir. See Brake Fluid
0 238.
11. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid
0 236.