ECU GMC YUKON 2006 Workshop Manual

Notice:Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.
The label will help you decide how much cargo and
installed equipment your truck can carry.
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.
If you put things inside your vehicle — like suitcases,
tools, packages, or anything else — they go as fast
as the vehicle goes. If you have to stop or turn quickly,
or if there is a crash, they will 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.
Do not leave an unsecured child restraint
in your vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
Do not leave a seat folded down unless
you need to.
There is also important loading information for off-road
driving in this manual. See “Loading Your Vehicle
for Off-Road Driving” underOff-Road Driving on
page 4-16.
4-50

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.
Q:What is front axle reserve capacity, and how do
I calculate it?
A: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 Certication/Tire
label, as shown.
United States
Canada
4-52

Four-Wheel-Drive Vehicles (NP8)
Use the following procedure to tow your vehicle:
1. Shift the transmission to PARK (P).
2. Turn the engine off, but leave the ignition on.
3. Firmly set the parking brake.
4. Securely attach the vehicle being towed to the
tow vehicle.
{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle to
roll even if the transmission is in PARK (P).
You or others could be injured. Make sure the
parking brake is rmly set before you shift
the transfer case to NEUTRAL.
5. Shift the transfer case to NEUTRAL (N). See
Four-Wheel Drive on page 2-26for the proper
procedure to select the NEUTRAL (N) position
for your vehicle.
6. Release the parking brake only after the vehicle
being towed is rmly attached to the towing
vehicle.
7. Turn the ignition off.
4-57

Dolly Towing
Two-Wheel-Drive Vehicles
Notice:If you tow a two-wheel-drive vehicle with
the rear wheels on the ground, the transmission
could be damaged. The repairs would not be
covered by your warranty. Never tow your vehicle
with the rear wheels on the ground.
Two-wheel-drive vehicles should not be towed with
the rear wheels on the ground. Two-wheel-drive
transmissions have no provisions for internal lubrication
while being towed.
Two-wheel-drive vehicles can be towed on a dolly
with the front wheels on the ground provided that
the wheels are straight and the steering column has
been locked.
Four-Wheel-Drive Vehicles
If your vehicle is equipped with StabiliTrak®,itisnot
designed to be dolly towed. If you need to tow your
vehicle, see “Dinghy Towing” earlier in this section.If your vehicle is not equipped with StabiliTrak
®,
use the following procedure to tow your vehicle:
1. Drive the vehicle up onto the tow dolly.
2. Shift the transmission to PARK (P).
3. Turn the engine off, but leave the ignition on.
4. Firmly set the parking brake.
5. Securely attach the vehicle being towed to
the tow dolly.
4-58

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 2-35. 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 3-22.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 all trailer hitch parts 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.
4-70

{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap — even a little — when the engine and
radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the
FULL COLD mark.
If your vehicle is equipped with a low coolant sensor
and the LOW COOLANT LEVEL message comes
on and stays on, it means you are low on engine
coolant. See “LOW COOLANT LEVEL” underDIC
Warnings and Messages on page 3-56.
Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixture at the surge tank, but only when the
engine is cool.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.
When replacing the pressure cap, make sure it is
hand-tight and fully seated.
Coolant Surge Tank Pressure Cap
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.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank. SeeEngine
Compartment Overview on page 5-12for more
information on location.
5-27

A. Low-Beam Headlamp
B. High-Beam Headlamp
3. Pull the headlamp assembly out.
4. Unplug the electrical connector.
5. Turn the bulb counterclockwise and remove it from
the headlamp assembly.
6. Put the new bulb into the headlamp assembly and
turn it clockwise until it is tight.
7. Plug in the electrical connector.
8. Put the headlamp assembly back into the vehicle.
9. Install and turn the two pins to secure the headlamp
assembly.
Front Turn Signal, Sidemarker and
Daytime Running Lamps
A. Sidemarker Lamp
B. Retainer ClipC. Front Turn Signal Lamp
D. Daytime Running
Lamp (DRL)
To replace a front turn signal, sidemarker or DRL bulb,
do the following:
1. Open the hood. SeeHood Release on page 5-11
for more information.
2. Remove the headlamp assembly as described
previously. SeeHeadlamps on page 5-50for
more information.
5-51

Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for wear
and cracking. SeeScheduled Maintenance on page 6-4
for more information.
Replacement blades come in different types and
are removed in different ways. For proper type and
length, seeNormal Maintenance Replacement Parts
on page 6-15.
To replace the windshield wiper blade assembly
do the following:
1. Lift the wiper arm away from the windshield.2. Push the release lever (B) to disengage the hook
and push the wiper arm (A) out of the blade (C).
3. Push the new wiper blade securely on the wiper arm
until you hear the release lever click into place.
To replace the rear wiper blade, follow the steps
listed above.
5-56

Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km).
Any time you notice unusual wear, rotate your tires
as soon as possible and check wheel alignment. Also
check for damaged tires or wheels. SeeWhen It Is Time
for New Tires on page 5-69andWheel Replacement
on page 5-73for more information.
Make sure the spare tire is stored securely. Push,
pull, and then try to rotate or turn the tire. If it moves,
use the ratchet/wheel wrench to tighten the cable.
SeeChanging a Flat Tire on page 5-76.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The rst rotation
is the most important. SeeScheduled Maintenance
on page 6-4.When rotating your vehicle’s tires, always use the
correct rotation pattern shown here.
Do not include the spare tire in the tire rotation.
After the tires have been rotated, adjust the front
and rear ination pressures as shown on the tire and
loading information label. SeeLoading Your Vehicle on
page 4-46andInation - Tire Pressure on page 5-63,
for more information.
5-68

CAUTION: (Continued)
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.
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 nd traction devices that will t,
install them on the rear tires.
Notice:If you have a tire size other than
P265/75R16, LT265/75R16, P265/70R16, P265/70R17,
or P275/55R20 use tire chains only where legal
and only when you must. Use chains that are the
proper size for your 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 at tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
Steer to maintain lane position, and then gently brake
to a stop well out of the traffic lane.
5-75