2003 GMC YUKON Owner's Manual

Vehicle* Axle Ratio Maximum Trailer Weight GCWR
8100 V8 3.73 10,400 lbs. (4 717 kg) 17,000 lbs. (7 718 kg)
(Suburban/Yukon XL)†4.10 12,000 lbs. (5 448 kg) 14,000 lbs. (6 356 kg)
*Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,500 lbs. (681 kg) maximum.
**GCWR limited to 14,000 lbs. (6 356 kg) on vehicles with Z83 suspension.
†2500 Suburban/Yukon XL (2WD) equipped with Z83 base suspension limited to 7,900 lbs. (3 583 kg) trailer.
Vehicle* Axle Ratio Maximum Trailer Weight GCWR
K—2500 (4WD)*
6000 V8
(Suburban/Yukon XL)†3.73
4.107,600 lbs. (3 447 kg)
9,600 lbs. (4 354kg)14,000 lbs. (6 356 kg)
16,000 lbs. (7 264 kg)**
6,000 V8 w/4WS3.73
4.107,300 lbs. (3 311 kg)
9,300 lbs. (4 218 kg)14,000 lbs. (6 350 kg)
16, 000 lbs (7 257 kg)
8100 V83.73
4.1010,100 lbs. (4 581 kg)
12,000 lbs. (5 448 kg)17,000 lbs. (7 718 kg)
19,000 lbs. (8 626 kg)
*Tongue weight should be 10 percent to 15 percent of trailer weight up to 1,500 lbs. (681 kg)
**GCWR limited to 14,000 lbs. (6 356 kg) on vehicles with Z83 suspension.
†2500 Suburban/Yukon XL (4WD) equipped with Z83 base suspension limited to 7,900 lbs. (3 586 kg) trailer.
The Gross Combination Weight Rating (GCWR) is the
total allowable weight of the completely loaded
vehicle and trailer including any passengers, cargo,
equipment and conversions. The GCWR for your vehicle
should not be exceeded.
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
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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. See Loading Your Vehicle for more information about
your vehicle’s maximum load capacity.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 label at the rear edge of the driver’s door or
see Tire Loading for more information. Then be sure
you don’t go over the GVW limit for your vehicle,
including the weight of the trailer tongue. If you use a
weight distributing hitch, make sure you don’tgo
over the rear axle limit before you apply the weight
distribution spring bars.
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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 use a step-bumper hitch, your bumper could
be damaged in sharp turns. Make sure you have
ample room when turning to avoid contact between
the trailer and the bumper.
If you’ll be pulling a trailer that, when loaded, will
weigh more than 5,000 lbs (2 270 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. SeeEngine Exhaust
on page 2-38. Dirt and water can, too.
Safety Chains
You should always attach safety 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.
If you are towing a trailer up to 5,000 lbs (2 270 kg) with
a factory-installed step bumper, you may attach the
safety chains to the attaching points on the bumper. If
you are towing a trailer up to your vehicle’s trailer rating
limit, you may attach the safety chains to the attaching
point on the hitch platform. If you are towing with
an aftermarket hitch, following the trailer or hitch
manufacturer’s recommendation for attaching safety
chain. Always leave just enough slack so you can turn
with your rig. Never allow safety chains to drag on
the ground.
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Trailer Brakes
If your trailer weighs more than 2,000 lbs. (900 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.
If your vehicle is equipped with Stabilitrak
®, your trailer
cannot tap into the vehicle’s hydraulic brake system.
Your trailer brake system can tap into the vehicle’s
hydraulic brake system only if:
The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
The trailer’s brake system will use less than
0.02 cubic inches (0.3 cc) ofuid from your vehicle’s
master cylinder. Otherwise, both braking systems
won’t work well. You could even lose your brakes.
If everything checks out this far, make the brake tap at
the port on the master cylinder that sends theuid
to the rear brakes. But don’t use copper tubing for this.
If you do, it will bend andnally break off. Use steel
brake tubing.
Driving with a Trailer
{CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon
monoxide (CO) could come into your vehicle.
You can’t see or smell CO. It can cause
unconsciousness or death. See“Engine
Exhaust”in the Index. To maximize your safety
when towing a trailer:
•Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
•Keep the rear-most windows closed.
•If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
the climate control setting for maximum air
because it only recirculates the air inside
your vehicle. See“Climate Controls”in the
Index.
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Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the trailer.
And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer moving and
then apply the trailer brake controller by hand to be
sure the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as
you would when driving your vehicle without a trailer.
This can help you avoid situations that require
heavy braking and sudden turns.
Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re a good deal
longer, you’ll need to go much farther beyond the
passed vehicle before you can return to your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, just move that hand
to the left. To move the trailer to the right, move your
hand to the right. Always back up slowly and, if possible,
have someone guide you.
If your vehicle is equipped with four-wheel steering and
if you use it while backing your trailer the same rules
apply. However, with four-wheel steering your rig
will respond more quickly and it may take additional
practice to get used to backing up with four-wheel
steering.
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Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns
than normal. Do this so your trailer won’t strike
soft shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well in
advance.
Turn Signals When Towing a Trailer
The arrows on your instrument panel willash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will alsoash, telling other drivers
you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel willash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
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).
You may also want to activate the tow/haul mode if the
transmission shifts too often. See“Tow/Haul Mode”
for more information.
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 you turn your
engine off immediately after towing at high altitude
on steep uphill grades, your 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 PARK (P) for a
few minutes before turning the engine off. If you do get
the overheat warning, seeEngine Overheating on
page 5-29.
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Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brake, but don’t shift into
PARK (P) yet.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P).
5. If you have a four-wheel-drive vehicle, be sure the
transfer case is in a drive gear and not in
NEUTRAL.
6. Release the regular brakes.
{CAUTION:
It can be dangerous to get out of your vehicle if
the shift lever is not fully in PARK (P) with the
parking brakefirmly set. Your vehicle can roll.
If you have left the engine running, the vehicle
can move suddenly. You or others could be
injured. To be sure your vehicle won’t move,
even when you’re on fairly level ground, use the
steps that follow.
Always put the shift lever fully in PARK (P) with
the parking brakefirmly set.
If the transfer case on four-wheel drive vehicles
is in NEUTRAL, your vehicle will be free to roll,
even if your shift lever is in PARK (P). So, be
sure the transfer case is in a drive gear—not in
NEUTRAL.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
start your engine,
shift into a gear, and
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
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmissionuid (don’t overll),
engine oil, axle lubricant, belts, cooling system and brake
system. Each of these is covered in this manual, and the
Index will help yound them quickly. If you’re trailering,
it’s a good idea to review these sections before you start
your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
Your vehicle is equipped with the following wiring
harnesses for towing a trailer.
Basic Trailer Wiring
The trailer wiring harness, with a seven-pin connector,
is located at the rear of the vehicle and is tied to
the vehicle’s frame. The harness connector can be
plugged into a seven-pin universal heavy-duty trailer
connector available through your dealer.
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