2012 GMC SAVANA Owner's Manual

Black plate (49,1)GMC Savana Owner Manual - 2012 - 2nd - 11/11/11
Driving and Operating 9-49
When towing at high altitude on
steep uphill grades, consider the
following: Engine coolant will boil at
a lower temperature than at normal
altitudes. If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the
vehicle may show signs similar to
engine overheating. To avoid this,
let the engine run while parked,
preferably on level ground, with the
automatic transmission in P (Park)
for a few minutes before turning the
engine off. If the overheat warning
comes on, seeEngine Overheating
on page 10‑23.Parking on Hills
{WARNING
Parking the vehicle on a hill with
the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface. If parking the rig on a hill:
1. Press the brake pedal, but do
not shift the transmission into
P (Park) yet. Turn the wheels
into the curb if facing downhill or
into traffic if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the brake pedal
until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake and shift
into P (Park).
5. Release the brake pedal.

Black plate (50,1)GMC Savana Owner Manual - 2012 - 2nd - 11/11/11
9-50 Driving and Operating
Leaving After Parking on a Hill
1. Apply and hold the brake pedalwhile you:
1.1. Start the engine.
1.2. Shift into a gear.
1.3. Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See this
manual's Maintenance Schedule or
Index for more information. 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 for more information.
{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.

Black plate (51,1)GMC Savana Owner Manual - 2012 - 2nd - 11/11/11
Driving and Operating 9-51
Notice: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” that
appears later in this section.
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 for more
information. 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 (52,1)GMC Savana Owner Manual - 2012 - 2nd - 11/11/11
9-52 Driving and Operating
VehicleAxle Ratio Maximum Trailer Weight GCWR*
G1500 Cargo Van 2WD 4.3L V6 3.421 950 kg (4,300 lbs) 4 309 kg (9,500 lbs)
5.3L V8 3.42
3.733 039 kg (6,700 lbs) 5 443 kg (12,000 lbs)
H1500 Cargo Van AWD 5.3L V8 3.422 948 kg (6,500 lbs) 5 443 kg (12,000 lbs)
G1500 Passenger Van 2WD
5.3L V8 3.42
3.73
2 812 kg (6,200 lbs) 5 443 kg (12,000 lbs)
H1500 Passenger Van AWD
5.3L V8 3.42
3.732 722 kg (6,000 lbs) 5 443 kg (12,000 lbs)
G2500 Cargo Van 2WD Short Wheelbase 4.8L V8 3.423 357 kg (7,400 lbs) 5 897 kg (13,000 lbs)
6.0L V8 3.424 536 kg (10,000 lbs) 7 257 kg (16,000 lbs)
G2500 Cargo Van 2WD Long Wheelbase
4.8L V8 3.423 266 kg (7,200 lbs) 5 897 kg (13,000 lbs)
6.0L V8 3.424 536 kg (10,000 lbs) 7 257 kg (16,000 lbs)

Black plate (53,1)GMC Savana Owner Manual - 2012 - 2nd - 11/11/11
Driving and Operating 9-53
VehicleAxle Ratio Maximum Trailer Weight GCWR*
G2500 Passenger Van 2WD Short Wheelbase 4.8L V8 3.423 039 kg (6,700 lbs) 5 897 kg (13,000 lbs)
6.0L V8 3.424 445 kg (9,800 lbs) 7 257 kg (16,000 lbs)
G3500 Cargo Van 2WD Short Wheelbase 4.8L V8 3.423 357 kg (7,400 lbs) 5 897 kg (13,000 lbs)
6.0L V8 3.424 536 kg (10,000 lbs) 7 257 kg (16,000 lbs)
G3500 Cargo Van 2WD Long Wheelbase 4.8L V8 3.423 221 kg (7,100 lbs) 5 897 kg (13,000 lbs)
6.0L V8 3.424 536 kg (10,000 lbs) 7 257 kg (16,000 lbs)
G3500 Passenger Van 2WD Short Wheelbase 6.0L V8 3.424 400 kg (9,700 lbs) 7 257 kg (16,000 lbs)
G3500 Passenger Van 2WD Long Wheelbase 6.0L V8 3.424 218 kg (9,300 lbs) 7 257 kg (16,000 lbs)
*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.

Black plate (54,1)GMC Savana Owner Manual - 2012 - 2nd - 11/11/11
9-54 Driving and Operating
Ask your dealer for our trailering
information or advice, or write us at
our Customer Assistance Offices.
SeeCustomer Assistance Offices
on page 13‑3 for more information.
Weight of the Trailer Tongue
The tongue load (A) 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 9‑10
for more information about the
vehicle's maximum load capacity.
The trailer tongue weight (A) should
be 10 percent to 15 percent of the
total loaded trailer weight (B), up to
a maximum of 181 kg (400 lbs) with
a weight carrying hitch. The trailer
tongue weight (A) should be
10 percent to 15 percent of the total
loaded trailer weight (B), up to a
maximum of 454 kg (1,000 lbs) 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.

Black plate (55,1)GMC Savana Owner Manual - 2012 - 2nd - 11/11/11
Driving and Operating 9-55
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 seeVehicle Load
Limits on page 9‑10. 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
It is important to have the correct
hitch equipment. Crosswinds, large
trucks going by and rough roads are
a few reasons why the right hitch is
needed.
Weight‐Distributing Hitches
and Weight Carrying Hitches
A. Body to Ground Distance
B. Front of Vehicle
When using a weight-distributing
hitch, the hitch must be adjusted so
the distance (A) remains the same
both before and after coupling the
trailer to the tow vehicle. If a step-bumper hitch will be used,
the bumper could be damaged in
sharp turns. Make sure there
is ample room when turning to avoid
contact between the trailer and the
bumper.
If the loaded trailer being pulled
will weigh more than 2 270 kg
(5,000 lbs), be sure to use a
properly mounted weight-distributing
hitch and sway control of the proper
size. This equipment is very
important for proper vehicle loading
and good handling when driving.
Always use a sway control if the
trailer will weigh more than these
limits. Ask a hitch dealer about sway
controls.
Will any holes need to be made in
the body of the vehicle when a
trailer hitch is installed?

Black plate (56,1)GMC Savana Owner Manual - 2012 - 2nd - 11/11/11
9-56 Driving and Operating
If using the wiring provided with the
factory-installed trailering package,
no holes need to be made in the
body of the vehicle. However, if an
aftermarket hitch is installed, holes
may need to be made in the body.
If holes are made in the body, then
be sure to seal the holes later when
the hitch is removed. If the holes are
not sealed, deadly carbon monoxide
(CO) from the engine's exhaust can
get into the vehicle as well as dirt
and water. See“Carbon Monoxide”
under Engine Exhaust on
page 9‑24.
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 lbs) 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 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.
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 *