2011 GMC YUKON ECU

Black plate (76,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-76 Driving and Operating
Driving with a Trailer
{WARNING
When towing a trailer, exhaust
gases may collect at the rear
of the vehicle and enter if the
liftgate, trunk/hatch, or rear-most
window is open.
Engine exhaust contains Carbon
Monoxide (CO) which cannot be
seen or smelled. It can cause
unconsciousness and even death.
To maximize safety when towing
a trailer:
.Have the exhaust system
inspected for leaks and make
necessary repairs before
starting a trip.
.Never drive with the liftgate,
trunk/hatch, or rear-most
window open.(Continued)
WARNING (Continued)
.Fully open the air outlets
on or under the instrument
panel.
.Adjust the Climate Control
system to a setting that
brings in only outside air
and set the fan speed to the
highest setting. See Climate
Control System in the Index.
For more information about
Carbon Monoxide, see Engine
Exhaust on page 9‑36.
Towing a trailer requires a certain
amount of experience. The
combination you are driving is
longer and not as responsive as the
vehicle itself. Get acquainted with
the handling and braking of the rig
before setting out for the open road. Before starting, check all trailer
hitch parts and attachments, safety
chains, electrical connectors,
lamps, tires and mirrors. If the
trailer has electric brakes, start the
combination moving and then apply
the trailer brake controller by hand
to be sure the brakes work.
During the trip, check occasionally
to be sure that the load is secure
and the lamps and any trailer
brakes still work.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle without a trailer.
This can help to avoid heavy
braking and sudden turns.
Passing
More passing distance is needed
when towing a trailer. The
combination will not accelerate
as quickly and is longer so it is
necessary to go much farther
beyond the passed vehicle before
returning to the lane.

Black plate (95,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-95
Say, for example, you have a 318 kg
(700 lb) snow plow. The total weight
of all occupants and cargo inside
the cab should not exceed 135 kg
(300 lb). This means that you may
only be able to carry one passenger.
But, even this may be too much if
there is other equipment already
adding to the weight of the vehicle.
Here are some guidelines for safely
carrying a snow plow on the vehicle:
.Make sure the weight on the
front and rear axles does not
exceed the axle rating for each.
.For the front axle, if more cargo
or passengers must be carried,
appropriate counter ballast must
be installed rear of the rear axle.
Counter ballast must be properly
secured so it will not move
during driving.
.Follow the snow plow
manufacturer's
recommendations regarding
rear ballast. Rear ballast may
be required to ensure a proper
front and rear weight distribution
ratio, even though the actual
weight at the front axle may be
less than the front axle rating.
.The snow plow manufacturer
or installer can assist in
determining the amount of rear
ballast required, to help make
sure the snowplow/vehicle
combination does not exceed
the GVW rating, the front and
rear axle ratings, and the front
and rear weight distribution ratio.
.The total vehicle must not
exceed the GVW rating.Front axle reserve capacity is the
difference between the front Gross
Axle Weight Rating (GAWR) and the
front axle weight of the vehicle with
full fuel and passengers. Basically, it
is the amount of weight that can be
added to the front axle before
reaching the front GAWR.
The front axle reserve capacity
for the vehicle can be found
in the lower right corner of the
Certification/Tire label, as shown.
United States

Black plate (21,1)GMC Yukon/Yukon XL Owner Manual - 2011
Vehicle Care 10-21
4. With the coolant surge tankpressure cap off, start the
engine and let it run until the
upper radiator hose can be felt
getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge tank
until the level reaches the FULL
COLD mark. 5. Replace the pressure cap.
Be sure the pressure cap is
hand-tight and fully seated.
6. Verify coolant level after engine is shut off and the coolant is
cold. If necessary, repeat coolant
fill procedure Steps 1 through 6.
Notice: If the pressure cap is
not tightly installed, coolant loss
and possible engine damage may
occur. Be sure the cap is properly
and tightly secured.
Engine Overheating
The vehicle has several indicators
to warn of engine overheating.
There is a coolant temperature
gauge on your vehicle's instrument
panel. See Engine Coolant
Temperature Gauge on page 5‑16. In addition, ENGINE OVERHEATED
STOP ENGINE, ENGINE
OVERHEATED IDLE ENGINE, and
a ENGINE POWER IS REDUCED
message comes on in the Driver
Information Center (DIC) on the
instrument panel. See
Engine
Cooling System Messages on
page 5‑40 andEngine Power
Messages on page 5‑41.
If the decision is made not to lift the
hood when this warning appears,
but instead get service help right
away. See Roadside Assistance
Program on page 13‑6.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.

Black plate (70,1)GMC Yukon/Yukon XL Owner Manual - 2011
10-70 Vehicle Care
Tire Chains
If your vehicle is a Hybrid, see
the Hybrid Supplement for more
information.
{WARNING
If your vehicle has P265/65R18 or
P275/55R20 size tires, do not use
tire chains. They can damage
your vehicle because there is not
enough clearance. Tire chains
used on a vehicle without the
proper amount of clearance can
cause damage to the brakes,
suspension, or other vehicle
parts. The area damaged by the
tire chains could cause you to
lose control of your vehicle and
you or others may be injured in a
crash.(Continued)
WARNING (Continued)
Use another type of traction
device only if its manufacturer
recommends it for use on your
vehicle and tire size combination
and road conditions. Follow
that manufacturer's instructions.
To help avoid damage to your
vehicle, drive slowly, readjust
or remove the device if it is
contacting your vehicle, and do
not spin your vehicle's wheels.
If you do find traction devices that
will fit, install them on the rear
tires. Notice:
If your vehicle has
P265/70R17 size tires, use tire
chains only where legal and
only when you must. Use chains
that are the proper size for your
vehicle's tires. Install them on the
rear tires only.
Do not use chains on the front
tires.
Tighten them as tightly as
possible with the ends securely
fastened. Drive slowly and
follow the chain manufacturer's
instructions. If you can hear the
chains contacting your vehicle,
stop and retighten them. If the
contact continues, slow down
until it stops. Driving too fast or
spinning the wheels with chains
on will damage your vehicle.

Black plate (82,1)GMC Yukon/Yukon XL Owner Manual - 2011
10-82 Vehicle Care
Pull the pin through the center of
the wheel. Tilt the retainer down
through the center wheel
opening.
Make sure the retainer is fully
seated across the underside of
the wheel.
3. Assemble the two jack handleextensions (D) and wheel
wrench (E) as shown.
4. Insert the open end of theextension (J) through the hole in
the rear bumper (I) (hoist shaft
access hole).
5. Raise the tire part way upward. Make sure the retainer is seated
in the wheel opening.
6. Raise the tire fully against the underside of the vehicle by
turning the wheel wrench
clockwise until you hear
two clicks or feel it skip twice.
You cannot overtighten the
cable.7. Make sure the tire is storedsecurely. Push, pull (A), and then
try to turn (B) the tire. If the tire
moves, use the wheel wrench to
tighten the cable.
8. Reinstall the spare tire lock.
9. Reinstall the hoist shaft access cover.

Black plate (83,1)GMC Yukon/Yukon XL Owner Manual - 2011
Vehicle Care 10-83
To store the tools, do the following:
A. Wheel Blocks
B. Tool Bag with Jack Tools
C. Retaining Bracket
D. Wing Nut Retaining Tool Bag
E. Jack
F. Wing Nut Retaining WheelBlocks
G. Jack Knob
1. Return the tools (wheel wrench, jack handle, and jack handle
extensions) to the tool bag (B). 2. Assemble wheel blocks (A) and
jack (E) together with the
wing nut (F).
3. Position the jack (E) and wheel blocks (A) in the driver side trim
panel over the wheelhouse.
4. Turn the jack knob (G) clockwise until the jack is secured tight in
the mounting bracket. Be sure
to position the holes in the base
of the jack onto the pin in the
mounting bracket.
5. Use the retaining bracket (C) to fasten the tool bag (B) on the
stud and turn the wing nut (D)
clockwise to secure.
6. Return the storage tray to itsoriginal stored position.

Black plate (85,1)GMC Yukon/Yukon XL Owner Manual - 2011
Vehicle Care 10-85
7. Place the bottom edge of thejack (A) on the wheel blocks (B),
separating them so that the jack
is balanced securely.8. Attach the jack handle,extension, and wheel wrench to
the jack and place it (with the
wheel blocks) under the vehicle
toward the front of the rear
bumper.9. Position the center lift point ofthe jack under the center of the
spare tire.
10. Turn the wrench clockwise to raise the jack until it lifts the
end fitting.
11. Continue raising the jack until the spare tire stops moving
upward and is held firmly in
place. The secondary latch has
released and the spare tire is
balancing on the jack.

Black plate (94,1)GMC Yukon/Yukon XL Owner Manual - 2011
10-94 Vehicle Care
Dinghy Towing
Two-Wheel-Drive Vehicles and
Four-Wheel Drive Vehicles
with a Single Speed Automatic
Transfer Case
Notice:If the vehicle is towed
with all four wheels on the
ground, the drivetrain
components could be damaged.
The repairs would not be covered
by the vehicle warranty. Do
not tow the vehicle with all
four wheels on the ground. Two-wheel-drive vehicles and
four-wheel drive vehicles with a
single speed automatic transfer
case should not be towed with
all four wheels on the ground.
Two-wheel-drive transmissions have
no provisions for internal lubrication
while being towed. Four-wheel
drive vehicles with a single speed
automatic transfer case have no
neutral position and will spin the
transmission when the rear
wheels turn.
Four-Wheel Drive Vehicles
with a Two Speed Automatic
Transfer Case
Use the following procedure to
dinghy tow a four-wheel drive
vehicle with a two speed automatic
transfer case:
1. Position the vehicle being towed
behind the tow vehicle and shift
the transmission to P (Park).
2. Turn the engine off and firmly set the parking brake.
3. Securely attach the vehicle being towed to the tow vehicle.