ECU GMC YUKON XL 2010 Workshop Manual

Here are some guidelines for safely carrying a snow
plow on your 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
you in determining the amount of rear ballast
required, to help make sure your 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
your front Gross Axle Weight Rating (GAWR) and the
front axle weight of your vehicle with full fuel and
passengers. Basically, it is the amount of weight
you can add to your front axle before reaching your
front GAWR.
The front axle reserve capacity for your vehicle can be
found in the lower right corner of the Certification/Tire
label, as shown.United StatesCanada
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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.
{WARNING:
Shifting a four-wheel-drive vehicle's transfer case
into N (Neutral) can cause the vehicle to roll even
if the transmission is in P (Park). The driver or
others could be injured. Make sure the parking
brake is firmly set before the transfer case is
shifted to N (Neutral).
4. Shift the transfer case to N (Neutral). See “Shifting
into Neutral” under“Four-Wheel Drive” for the
proper procedure to select the Neutral position
for the vehicle.
5. Release the parking brake only after the vehicle being towed is firmly attached to the towing
vehicle.
6. Turn the ignition to LOCK/OFF and remove the key —the steering wheel will still turn.
After towing, see “Shifting Out of Neutral” under
“Four-Wheel Drive” for the proper procedure to take
the vehicle out of the Neutral position.
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Four-Wheel Drive Vehicles with a Two
Speed Automatic Transfer Case
Use the following procedure to dolly tow a four-wheel
drive vehicle from the front:1. Attach the dolly to the tow vehicle following the dolly manufacturer's instructions.
2. Drive the front wheels onto the dolly.
3. Shift the transmission to P (Park).
4. Firmly set the parking brake.
{WARNING:
Shifting a four-wheel-drive vehicle's transfer case
into N (Neutral) can cause the vehicle to roll even
if the transmission is in P (Park). The driver or
others could be injured. Make sure the parking
brake is firmly set before the transfer case is
shifted to N (Neutral).
5. Shift the transfer case to N (Neutral). See “Shifting
into N (Neutral)” under“Four-Wheel Drive”.
6. Secure the vehicle to the dolly following the manufacturer's instructions.
7. Release the parking brake only after the vehicle being towed is firmly attached to the towing
vehicle.
8. Turn the ignition to LOCK/OFF.
After towing, see “Shifting Out of N (Neutral)” under
“Four-Wheel Drive”.
5-45

Rear Towing (Rear Wheels Off the
Ground)Two-Wheel-Drive Vehicles and Four-Wheel
Drive Vehicles with a Single Speed
Automatic Transfer Case
Use the following procedure to dolly tow the vehicle
from the rear:1. Attach the dolly to the tow vehicle following the dolly manufacturer's instructions.
2. Drive the rear wheels onto the dolly.
3. Firmly set the parking brake. See Parking Brake
on page 3‑48.
4. Put the transmission in P (Park).
5. Secure the vehicle to the dolly following the manufacturer's instructions.
6. Use an adequate clamping device designed for towing to ensure that the front wheels are locked
into the straight position.
7. For four-wheel drive vehicles with a single speed automatic transfer case, turn the transfer case
knob to the Two-Wheel High position.
8. Turn the ignition to LOCK/OFF.
5-46

Four-Wheel Drive Vehicles with a
Two Speed Automatic Transfer Case
Use the following procedure to dolly tow a four-wheel
drive vehicle from the rear:1. Attach the dolly to the tow vehicle following the dolly manufacturer's instructions.
2. Drive the rear wheels onto the dolly.
3. Firmly set the parking brake. See Parking Brake
on page 3‑48.
4. Put the transmission in P (Park).
5. Secure the vehicle to the dolly following the manufacturer's instructions.
6. Use an adequate clamping device designed for towing to ensure that the front wheels are locked
into the straight position.
{WARNING:
Shifting a four-wheel-drive vehicle's transfer case
into N (Neutral) can cause the vehicle to roll even
if the transmission is in P (Park). The driver or
others could be injured. Make sure the parking
brake is firmly set before the transfer case is
shifted to N (Neutral).
7. Shift the transfer case to N (Neutral). See “Shifting
into N (Neutral)” under“Four-Wheel Drive”.
8. Turn the ignition to LOCK/OFF.
After towing, see “Shifting Out of N (Neutral)” under
“Four-Wheel Drive”.
5-47

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.
.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 3‑52. 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.
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4. With the coolant surge tank pressure cap off,start the engine and let it run until you can feel the
upper radiator hose 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 4‑38.
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 DIC Warnings and Messages on page 4‑61.
6-36

Reset the Tire Pressure Monitor System.
SeeTire Pressure Monitor Operation
on
page 6‑75
.
Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specifications
on page 6‑126.
{WARNING:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the
vehicle. In an emergency, you can use a
cloth or a paper towel to do this; but be
sure to use a scraper or wire brush later,
if needed, to get all the rust or dirt off.
See Changing a Flat Tire
on page 6‑88.
Make sure the spare tire is stored securely. Push,
pull, and then try to rotate or turn the tire. If it
moves, tighten the cable. See Storing a Flat or
Spare Tire and Tools
on page 6‑103.
When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions,
influence when you need new tires.
One way to tell when it is
time for new tires is to
check the treadwear
indicators, which appear
when your tires have only
1/16 inch (1.6 mm) or less
of tread remaining. Some
commercial truck tires
may not have treadwear
indicators.
6-79

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.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your vehicle's tires properly.
If air goes out of a tire, it is much more likely to leak out
slowly. But if you should ever have a blowout, here are
a few tips about what to expect and what to do:
If a front tire fails, the flat tire creates a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake
to a stop well out of the traffic lane. A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you would
use in a skid. In any rear blowout remove your foot from
the accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop, well off the road if possible.
{WARNING:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
If a jack is provided with the vehicle, it is designed
only for changing a flat tire. If it is used for
anything else, you or others could be badly
injured or killed if the vehicle slips off the jack.
If a jack is provided with the vehicle, only use it
for changing a flat tire.
If a tire goes flat, the next part shows how to use the
jacking equipment to change a flat tire safely.
6-87

3. Loosen the cable by turning the wrenchcounterclockwise three or four turns.
4. Repeat this procedure at least two times. If the spare tire lowers to the ground, continue with
Step 5 of Removing the Spare Tire and Tools
on
page 6‑89.
5. If the spare does not lower, turn the wrench counterclockwise until approximately 6 inches
(15 cm) of cable is exposed.
6. Stand the wheel blocks on their shortest ends, with the backs facing each other.
7. Place the bottomedge of the jack (A) on
the wheel blocks (B),
separating them so that
the jack is balanced
securely.
6-101