2003 GMC SAFARI Owner's Manual

Recreational Vehicle Towing
Recreational vehicle towing means towing your vehicle
behind another vehicle—such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as“dinghy towing”(towing your
vehicle with all four wheels on the ground) and“dolly
towing”(towing your vehicle with two wheels on
the ground and two wheels up on a device known as a
“dolly”).
Your vehicle was not designed to be towed with any of
its wheels on the ground. If your vehicle must be
towed, seeTowing Your Vehicle on page 4-28.
Notice:Towing an all-wheel-drive vehicle with all
four wheels on the ground, or even with only two of
its wheels on the ground, will damage drivetrain
components. Don’t tow an all-wheel-drive vehicle if
any of its wheels will be on the ground.
Loading Your Vehicle
The Certication/Tire label in your vehicle will look
similar to this example.
The Certication/Tire label is found on the rear edge of
the driver’s door. The label shows the size of your
original tires and the ination pressures needed to obtain
the gross weight capacity of your vehicle.
This is called the Gross Vehicle Weight Rating (GVWR).
The GVWR includes the weight of the vehicle, all
occupants, fuel, cargo and tongue weight, if pulling
a trailer.
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The Certication/Tire label also tells you the maximum
weights for the front and rear axles, called Gross Axle
Weight Rating (GAWR). Tond out the actual loads on
your front and rear axles, you need to go to a weigh
station and weigh your vehicle. Your dealer can help you
with this. Be sure to spread out your load equally on both
sides of the centerline.
Never exceed the GVWR for your vehicle, or the GAWR
for either the front or rear axle.
And, if you do have a heavy load, you should spread
it out.
{CAUTION:
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
GAWR. If you do, parts on your vehicle can
break, and it can change the way your vehicle
handles. These could cause you to lose
control and crash. Also, overloading can
shorten the life of your vehicle.
Using heavier suspension components to get added
durability might not change your weight ratings. Ask your
dealer to help you load your vehicle the right way.Notice:Your warranty does not cover parts or
components that fail because of overloading.
If you put things inside of your vehicle–like suitcases,
tools, packages, or anything else–they will go as
fast as the vehicle goes. If you have to stop or turn
quickly, or if there is a crash, they’ll keep going.
{CAUTION:
Things you put inside your vehicle can strike
and injure people in a sudden stop or turn, or
in a crash.
•Put things in the cargo area of your
vehicle. Try to spread the weight evenly.
•Never stack heavier things, like suitcases,
inside the vehicle so that some of them
are above the tops of the seats.
•Don’t leave an unsecured child restraint in
your vehicle.
•When you carry something inside the
vehicle, secure it whenever you can.
•Don’t leave a seat folded down unless you
need to.
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Payload
The Payload Capacity is shown on the Certication/Tire
label. This is the maximum load capacity that your vehicle
can carry. Be sure to include the weight of the people
inside as part of your load. If you added any accessories
or equipment after your vehicle left the factory, remember
to subtract the weight of these things from the payload.
Your dealer can help you with this.
Trailering Package
There is a load rating which includes the weight of the
vehicle and the trailer it tows. This rating is called
the Gross Combination Weight Rating (GCWR).
When you weigh your trailer, be sure to include the
weight of everything you put in it. And, remember
togure the weight of the people inside the vehicle as
part of your load.
Add-On Equipment
When you carry removable items, you may need to put
a limit on how many people you carry inside your
vehicle. Be sure to weigh your vehicle before you buy
and install the new equipment.
Towing a Trailer
{CAUTION:
If you don’t use the correct equipment and
drive properly, you can lose control when you
pull a trailer. For example, if the trailer is too
heavy, the brakes may not work well -- or even
at all. You and your passengers could be
seriously injured. Pull a trailer only if you have
followed all the steps in this section. Ask your
dealer for advice and information about towing
a trailer with your vehicle.
Notice:Pulling a trailer improperly can damage
your vehicle and result in costly repairs not covered
by your warranty. To pull a trailer correctly, follow
the advice in this part, and see your dealer for
important information about towing a trailer with
your vehicle. Additional rear axle maintenance
is required for a vehicle used to tow a trailer. See
“Scheduled Maintenance Services”in the Index.
To identify what the vehicle trailering capacity is for your
vehicle, you should read the information in“Weight of
the Trailer”that appears later in this section.
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If yours was built with trailering options, as many are,
it’s ready for heavier trailers. But trailering is different
than just driving your vehicle by itself. Trailering means
changes in handling, durability and fuel economy.
Successful, safe trailering takes correct equipment, and
it has to be used properly.
That’s the reason for this part. In it are 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
you pull a trailer.
If You Do Decide To Pull A Trailer
If you do, here are some important points:
There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will be legal, not only where you live
but also where you’ll be driving. A good source for
this information can be state or provincial police.
Consider using a sway control if your trailer will
weigh 2,000 lbs (900 kg) or less. You should
always use a sway control if your trailer will weigh
more than 2,000 lbs (900 kg). You can ask a
hitch dealer about sway controls.
Don’t tow a trailer at all during therst 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during therst 500 miles (800 km) that you
tow a trailer, don’t drive over 50 mph (80 km/h)
and don’t make starts at full throttle. This helps your
engine and other parts of your vehicle wear in at
the heavier loads.
You can tow in DRIVE (D). You may want to shift
the transmission to THIRD (3) or, if necessary, a
lower gear selection if the transmission shifts
too often (e.g., under heavy loads and/or hilly
conditions).
Three important considerations have to do with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle’s tires.
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Tow/Haul Mode
The tow/haul mode is a feature that assists when pulling
a heavy trailer. The purpose of the tow/haul mode is:
to reduce the frequency of shifts when pulling a
heavy trailer.
to provide the same shift feel when pulling a heavy
trailer as when the vehicle is unloaded.
to reduce the need to change throttle position when
pulling a heavy trailer.
This feature is turned on or off by pressing a button on
the column shift lever. When the feature is on, a
light on the instrument panel will illuminate to indicate
that the tow/haul mode has been selected.
SeeTow/Haul Mode Light on page 3-35. The tow/haul
mode is automatically turned off each time the vehicle is
started.
The tow/haul mode is most effective when the vehicle
and trailer combined weight is at least 75% of the Gross
Vehicle Weight Rating (GVWR) and the maximum
trailer weight rating for the vehicle.The tow/haul mode for hauling a heavy trailer is most
useful under the following conditions:
When driving through hilly terrain at speeds below
55 mph (88 km/h).
When driving in low speed or stop and go traffic
below 55 mph (88 km/h).
When driving in parking lots.
Operating in the tow/haul mode when not pulling a
heavy trailer will not cause damage to the vehicle, but
you may experience reduced fuel economy and
undesirable performance from the engine and
transmission. The tow/haul mode should be used only
when pulling a heavy trailer.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to pull
a trailer are all important. And, it can also depend
on any special equipment that you have on your vehicle.
The following chart shows how much your trailer can
weigh, based upon your vehicle model and options.
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Vehicle Axle RatioMax. Trailer Wt. (lbs)
(kg) GCWR (lbs) (kg)
Two-Wheel Drive (Cargo)3.42
3.735,300 (2406)
5,800 (2633)9,500 (4313)
10,000 (4540)
Two-Wheel Drive (Passenger)3.42
3.734,900 (2225)
5,400 (2452)9,500 (4313)
10,000 (4540)
All-Wheel Drive (Cargo)3.42
3.735,100 (2315)
5,600 (2542)9,500 (4313)
10,000 (4540)
All-Wheel Drive (Passenger)3.42
3.734,600 (2088)
5,100 (2315)9,500 (4313)
10,000 (4540)
Maximum trailer weight is calculated assuming the
driver and one passenger are 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.
You can ask your dealer for our trailering information or
advice, or you can write us at the address listed in
your Warranty and Owner Assistance Information
Booklet.
In Canada, write to:
General Motors of Canada Limited
Customer Communication Centre, 163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight
to measure because it affects the total or gross weight
of your vehicle. The Gross Vehicle Weight (GVW)
includes the curb weight of the vehicle, any cargo you
may carry in it, and the people who will be riding in
the vehicle. And if you will tow a trailer, you must add
the tongue load to the GVW because your vehicle will be
carrying that weight, too. SeeLoading Your Vehicle
on page 4-29for more information about your vehicle’s
maximum load capacity.
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If you’re using a weight-carrying or a weight-distributing
hitch, the trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight (B).
Do not exceed the maximum allowable tongue weight
for your vehicle.
After you’ve loaded your trailer, weigh the trailer and
then the tongue, separately, to see if the weights
are proper. If they aren’t, you may be able to get
them right simply by moving some items around in
the trailer.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the upper limit
for cold tires. You’llnd these numbers on the
Certication/Tire label at the rear edge of the driver’s
door or seeLoading Your Vehicle on page 4-29.
Then be sure you don’t go over the GVW limit for your
vehicle, including the weight of the trailer tongue.
Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads are
a few reasons why you’ll need the right hitch. Here
are some rules to follow:
If you’ll be pulling a trailer that, when loaded, will
weigh more than 2,000 lbs. (900 kg.), 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 you’re driving.
Will you have to make any holes in the body of
your vehicle when you install a trailer hitch?
If you do, then be sure to seal the holes later when
you remove the hitch. If you don’t seal them,
deadly carbon monoxide (CO) from your exhaust
can get into your vehicle. Dirt and water can, too.
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Safety Chains
You should always attach chains between your vehicle
and your 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. Instructions about safety chains may be
provided by the hitch manufacturer or by the trailer
manufacturer. Follow the manufacturer’s
recommendation for attaching safety chains and do not
attach them to the bumper. Always leave just enough
slack so you can turn with your rig. Never allow
safety chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 lbs (450 kg)
loaded, then it needs its own brakes—and they must
be adequate. Be sure to read and follow the instructions
for the trailer brakes so you’ll be able to install, adjust
and maintain them properly.Your trailer brake system can tap into your vehicle’s
hydraulic brake system, except:
Don’t tap into your vehicle’s brake system if the
trailer’s brake system will use more than 0.02 cubic
inch (0.3 cc) ofuid from your vehicle’s master
cylinder. If it does, both braking systems won’t work
well. You could even lose your brakes.
Will the trailer parts take 3,000 psi (20 650 kPa) of
pressure? If not, the trailer brake system must not
be used with your vehicle.
If everything checks out this far, then make the
brakeuid tap at the port on the master cylinder that
sendsuid to the rear brakes. But don’t use
copper tubing for this. If you do, it will bend and
nally break off. Use steel brake tubing.
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