2005 GMC YUKON Owner's Manual

Towing a Trailer
Do not tow a trailer during break-in. SeeNew Vehicle
Break-In on page 2-19for more information.
{CAUTION:
If you do not 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.
To identify the vehicle trailering capacity of your vehicle,
you should read the information in “Weight of the
Trailer” that appears later in this section.
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 acceleration, braking, 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.
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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. See “Hitches” later
in this section.
Don’t tow a trailer at all during the rst 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during the rst 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). See “Tow/Haul Mode” later in
this section.Three important considerations have to do with weight:
The weight of the trailer
The weight of the trailer tongue
The weight on your vehicle’s tires
Tow/Haul Mode
Tow/Haul is a feature that assists when pulling a heavy
trailer or a large or heavy load. The purpose of the
Tow/Haul mode is to:
Reduce the frequency and improve the predictability
of transmission shifts when pulling a heavy trailer or
a large or heavy load.
Provide the same solid shift feel when pulling a
heavy trailer or a large or heavy load as when
the vehicle is unloaded.
Improve control of vehicle speed while requiring
less throttle pedal activity when pulling a heavy
trailer or a large or heavy load.
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Your vehicle may be equipped with a button at the end of
the shift lever which, when pressed, enables tow/haul.
Your vehicle may be equipped with Autoride
®which
further improves your vehicle’s ride while towing. See
Autoride
®on page 4-66for more information. When the
button is pressed, a light on the instrument panel will
illuminate to indicate that Tow/Haul has been selected.
Tow/Haul may be turned off by pressing the button again,
at which time the indicator light on the instrument panel
will turn off. The vehicle will automatically turn off Tow/
Haul every time it is started.
Tow/Haul is designed to be most effective when the
vehicle and trailer combined weight is at least 75 percent
of the vehicle’s Gross Combined Weight Rating (GCWR).
See Weight of the Trailer later in this section. Tow/Haul is
most useful under the following driving conditions:
When pulling a heavy trailer or a large or heavy load
through rolling terrain.
When pulling a heavy trailer or a large or heavy load
in stop and go traffic.
When pulling a heavy trailer or a large or heavy load
in busy parking lots where improved low speed
control of the vehicle is desired.Operating the vehicle in tow/haul when lightly loaded or
with no trailer at all will not cause damage. However,
there is no benet to the selection of Tow/Haul when the
vehicle is unloaded. Such a selection when unloaded
may result in unpleasant engine and transmission driving
characteristics and reduced fuel economy. Tow/Haul
is recommended only when pulling a heavy trailer or a
large or heavy load.
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.
Use one of the following charts to determine how
much your vehicle can weigh, based upon your vehicle
model and options.
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.
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Vehicle* Axle Ratio Maximum Trailer Weight GCWR
C-1500 (2WD)*
4800 V83.23
3.735,700 lbs. (2 585 kg)
6,700 lbs. (3 039 kg)11,000 lbs. (4 990 kg)
12,000 lbs. (5 443 kg)
5300 V83.23
3.736,700 lbs. (3 039 kg)
7,700 lbs. (3 492 kg)12,000 lbs. (5 443 kg)
13,000 lbs. (5 897 kg)
5300 V8
(Extended Models)3.42
4.107,400 lbs. (3 356 kg)
8,400 lbs. (3 810 kg)13,000 lbs. (5 897 kg)
14,000 lbs. (6 350 kg)
Vehicle* Axle Ratio Maximum Trailer Weight GCWR
K-1500 (4WD)*
4800 V83.42
4.106,500 lbs. (2 948 kg)
7,500 lbs. (3 402 kg)12,000 lbs. (5 443 kg)
13,000 lbs. (5 897 kg)
5300 V83.42
4.107,500 lbs. (3 402 kg)
7,800 lbs. (3 538 kg)13,000 lbs. (5 897 kg)
14,000 lbs. (6 350 kg)
5300 V8
(Extended Models)3.42
4.107,200 lbs. (3 265 kg)
8,200 lbs. (3 719 kg)13,000 lbs. (5 897 kg)
14,000 lbs. (6 350 kg)
Vehicle* Axle Ratio Maximum Trailer Weight GCWR
C-2500 (2WD)*
6000 V8
(Extended Models)3.73
4.107,900 lbs. (3 583 kg)
9,900 lbs. (4 490 kg)14,000 lbs. (6 350 kg)
16,000 lbs. (7 257 kg)
6000 V8 w/4WS3.73
4.107,700 lbs. (3 493 kg)
9,700 lbs. (4 400 kg)14,000 lbs. (6 350 kg)
16,000 lbs. (7 257 kg)
8100 V8
(Extended Models)3.73
4.1010,600 lbs. (4 808 kg)
12,000 lbs. (5 443 kg)17,000 lbs. (7 711 kg)
19,000 lbs. (8 618 kg)
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Vehicle* Axle Ratio Maximum Trailer Weight GCWR
K-2500 (4WD)*
6000 V8
(Extended Models)3.73
4.107,600 lbs. (3 447 kg)
9,600 lbs. (4 354 kg)14,000 lbs. (6 350 kg)
16,000 lbs. (7 257 kg)
6000 V8 w/4WS3.73
4.107,400 lbs. (3 357 kg)
9,400 lbs. (4 264 kg)14,000 lbs. (6 350 kg)
16,000 lbs. (7 257 kg)
8100 V83.73
4.1010,300 lbs. (4 672 kg)
12,000 lbs. (5 443 kg)17,000 lbs. (7 711 kg)
19,000 lbs. (8 618 kg)
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. If you have a lot of options, equipment,
passengers or cargo in your vehicle, it will reduce the
tongue weight your vehicle can carry, which will
also reduce the trailer weight your vehicle can tow. 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.The trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight, up to a
maximum or 600 lbs (272 kg) with a weight carrying
hitch. The trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight, up to a
maximum of 1,000 lbs (453 kg) for the 1500 series
and up to a maximum of 1,500 lbs (680 kg) for the
2500 series with a weight distributing hitch.
Do not exceed the maximum allowable tongue weight
for your 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 you have loaded the trailer, weigh the trailer and
then the tongue separately, to see if the weights
are proper. If they are not, you may be able to get them
right 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’ll nd these numbers on the
Certication label at the rear edge of the driver’s door or
seeLoading Your Vehicle on page 4-51for more
information. Then be sure you don’t go over the GVW
limit for your vehicle, or the GAWR, including the weight
of the trailer tongue. If you use a weight distributing
hitch, make sure you don’t go 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 will need the right hitch.
Weight-Distributing Hitches and Weight
Carrying Hitches
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 you use a step-bumper hitch, 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 you will 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 driving. Always use a sway control if the trailer
will weigh more than these limits. You can ask a
hitch dealer about sway controls.
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 chains. Always
leave just enough slack so you can turn with your rig.
Never allow safety chains to drag on the ground. (A) Body to Ground Distance (B) Front of Vehicle
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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) of uid 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 the uid
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.
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 cannot see or smell CO. It can cause
unconsciousness or death. SeeEngine
Exhaust on page 2-39. 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. SeeClimate Control System
on page 3-21.
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