GMC SAVANA 2020 Owner's Manual

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
200 Driving and Operating
Maintenance when Trailer
Towing
The vehicle needs service more
often when used to tow trailers. See
Maintenance Schedule0304. It is
especially important to check the
automatic transmission fluid, engine
oil, axle lubricant, belts, cooling
system, and brake system before
and during each trip.
Check periodically that all nuts and
bolts on the trailer hitch are tight.
Engine Cooling when Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See Engine Overheating
0 234.
Trailer Towing
If equipped with a diesel engine,
see the Duramax diesel
supplement.
Caution
Towing a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To tow a trailer
correctly, follow the directions in
this section and see your dealer
for important information about
towing a trailer with the vehicle.
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. Read this section
carefully before pulling a trailer.
Trailer Weight
{Warning
Never exceed the towing capacity
for your vehicle.
Safe trailering requires monitoring
the weight, speed, altitude, road
grades, outside temperature,
dimensions of the front of the trailer,
and how frequently the vehicle is
used to tow a trailer.

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
202 Driving and Operating
5. Add the weight of hitchhardware such as a draw bar,
ball, load equalizer bars,
or sway bars.
6. Add the weight of any accessories or aftermarket
equipment added to the
vehicle.
The resulting weight cannot exceed
the GCWR value shown on the Tow
Rating Chart.
The gross combined weight can
also be confirmed by weighing the
truck and trailer on a public scale.
The truck and trailer should be
loaded for the trip with passengers
and cargo.
Gross Vehicle Weight
Rating (GVWR)
For information about the vehicle's
maximum load capacity, see Vehicle
Load Limits 0157. When calculating
the GVWR with a trailer attached,
the trailer tongue weight must be
included as part of the weight the
vehicle is carrying.
Maximum Trailer Weight
The maximum trailer weight rating 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 Tow Rating Chart to
determine how much the trailer can
weigh, based on the vehicle model
and options.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Driving and Operating 203
Tow Rating Chart
VehicleAxle Ratio Maximum Trailer Weight GCWR (a)
G2500 Cargo Van 2WD Short Wheelbase 4.3L V6 3.423 357 kg (7,400 lb) 5 897 kg (13,000 lb)
6.0L V8 3.424 536 kg (10,000 lb) 7 258 kg (16,000 lb)
G2500 Cargo Van 2WD Long Wheelbase 4.3L V6 3.423 220 kg (7,100 lb) 5 897 kg (13,000 lb)
6.0L V8 3.424 536 kg (10,000 lb) 7 258 kg (16,000 lb)
G2500 Passenger Van 2WD Short Wheelbase 4.3L V6 3.423 039 kg (6,700 lb) 5 897 kg (13,000 lb)
6.0L V8 3.424 355 kg (9,600 lb) 7 258 kg (16,000 lb)
G3500 Cargo Van 2WD Short Wheelbase
4.3L V6 3.423 357 kg (7,400 lb) 5 897 kg (13,000 lb)
6.0L V8 3.424 536 kg (10,000 lb) 7 258 kg (16,000 lb)
G3500 Cargo Van 2WD Long Wheelbase 4.3L V6 3.423 265 kg (7,200 lb) 5 897 kg (13,000 lb)
6.0L V8 3.424 536 kg (10,000 lb) 7 258 kg (16,000 lb)
G3500 Passenger Van 2WD Short Wheelbase 4.3L V6 3.423 039 kg (6,700 lb) 5 897 kg (13,000 lb)

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
204 Driving and Operating
Tow Rating Chart (cont'd)
VehicleAxle Ratio Maximum Trailer Weight GCWR (a)
6.0L V8 3.424 355 kg (9,600 lb) 7 258 kg (16,000 lb)
G3500 Passenger Van 2WD Long Wheelbase 4.3L V6 3.422 858 kg (6,300 lb) 5 897 kg (13,000 lb)
6.0L V8 3.424 173 kg (9,200 lb) 7 258 kg (16,000 lb)
3500 Series Cutaway –353 cm (139 in) Wheelbase
4.3L V6 3.42/3.73(b)5 897 kg (13,000 lb)
6.0L V8 3.42/3.73(b)7 258 kg (16,000 lb)
3500 Series Cutaway –404 cm (159 in) Wheelbase
4.3L V6 3.42/3.73(b)5 897 kg (13,000 lb)
6.0L V8 3.42/3.73(b)7 258 kg (16,000 lb)
6.0L V8
(5 579 kg (12,300 lb) GVWR) 4.10
(b)8 618 kg (19,000 lb)
6.0L V8
(6 441 kg (14,200 lb) GVWR) 4.10
(b)9 072 kg (20,000 lb)
3500 Series Cutaway –450 cm (177 in) Wheelbase
6.0L V8 3.42/3.73(b)7 258 kg (16,000 lb)
6.0L V8
(5 579 kg (12,300 lb) GVWR) 4.10
(b)8 618 kg (19,000 lb)

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Driving and Operating 205
Tow Rating Chart (cont'd)
VehicleAxle Ratio Maximum Trailer Weight GCWR (a)
6.0L V8
(6 441 kg (14,200 lb) GVWR) 4.10
(b)9 072 kg (20,000 lb)
(a) 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.
(b) Maximum Trailer Weight cannot be provided because total vehicle weight is unknown.
The bumper on this vehicle is not
designed to tow a trailer.
Maximum Trailer Tongue
Weight Rating
The Maximum Trailer Tongue
Weight Rating is the allowable
trailer tongue weight that the vehicle
can support using a conventional trailer hitch. It may be necessary to
reduce the overall trailer weight to
stay within the maximum trailer
tongue weight rating while still
maintaining the correct trailer load
balance.
Do not exceed a maximum trailer
tongue weight of 454 kg (1,000 lb).

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
206 Driving and Operating
Vehicle Series Hitch Type Maximum Tongue Weight
2500/3500 Weight -
Carrying 181 kg (400 lb)
2500/3500 Weight -
Distributing 454 kg (1,000 lb)
The trailer tongue weight contributes
to the Gross Vehicle Weight (GVW).
GVW includes the curb weight of
your vehicle, any passengers,
cargo, equipment, and the trailer
tongue weight. Vehicle options,
passengers, cargo, and equipment
reduce the maximum allowable
tongue weight the vehicle can carry,
which also reduces the maximum
allowable trailer weight.
Trailer Load Balance
The correct trailer load balance
must be maintained to ensure trailer
stability. Incorrect load balance is a
leading cause of trailer sway.The trailer tongue weight (1) should
be 10–15% of the loaded trailer
weight (2). Some specific trailer
types, such as boat trailers, fall
outside of this range. Always refer
to the trailer owner ’s manual for the
recommended trailer tongue weight for each trailer. Never exceed the
maximum loads for your vehicle,
hitch, and trailer.
After loading the trailer, separately
weigh the trailer and then the trailer
tongue and calculate the trailer load
balance percentage to see if the
weights and distribution are
appropriate for your vehicle. If the
trailer weight is too high, it may be
possible to transfer some of the
cargo into your vehicle. If the trailer
tongue weight is too high or too low,
it may be possible to rearrange
some of the cargo inside of the
trailer.
Do not exceed the maximum
allowable tongue weight for your
vehicle. Use the shortest hitch
extension available to position the
hitch ball closer to your vehicle. This
will help reduce the effect of the
trailer tongue weight on the trailer
hitch and the rear axle.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Driving and Operating 207
If a cargo carrier is used in the
trailer hitch receiver, choose a
carrier that positions the load as
close to the vehicle as possible.
Make sure the total weight,
including the carrier, is no more than
half of the maximum allowable
tongue weight for the vehicle or
227 kg (500 lb), whichever is less.
Rear Gross Axle Weight Rating
(GAWR-RR)
The GAWR-RR is the total weight
that can be supported by the rear
axle of the vehicle. Do not exceed
the GAWR-RR for the vehicle, with
the tow vehicle and trailer fully
loaded for the trip including the
weight of the trailer tongue. If using
a weight-distributing hitch, do not
exceed the GAWR-RR before
applying the weight distribution
spring bars.Ask your dealer for trailering
information or assistance.
Towing Equipment
Hitches
Always use the correct hitch
equipment for your vehicle.
Crosswinds, large trucks going by,
and rough roads can affect the
trailer and the hitch.Proper hitch equipment for your
vehicle helps maintain combination
control. Many trailers can be towed
using a weight-carrying hitch which
has 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 between your vehicle
and trailer axles. See
“Maximum
Trailer Tongue Weight Rating” under
Trailer Towing 0200 for weight limits
with various hitch types.
Never attach rental hitches or other
bumper-type hitches. Only use
frame-mounted hitches that do not
attach to the bumper.
Consider using mechanical sway
controls with any trailer. Ask a
trailering professional about sway
controls or refer to the trailer
manufacturer's recommendations
and instructions.

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