tow GMC YUKON 2007 Repair Manual

5. If the uid level is below the COLD check
band, add only enough uid as necessary
to bring the level into the COLD band. It does
not take much uid, generally less than
one pint (0.5L). Do not overll.
6. Perform a hot check at the rst opportunity
after the transmission reaches a normal
operating temperature between 160°F to
200°F (71°C to 93°C).
7. If the uid level is in the acceptable range,
push the dipstick back in all the way, then
ip the handle down to lock the dipstick
in place.
Hot Check Procedure
Use this procedure to check the transmission uid
level when the transmission uid temperature is
between 160°F and 200°F (71°C and 93°C).
The hot check is the most accurate method to
check the uid level. The hot check should be
performed at the rst opportunity in order to verify
the cold check. The uid level rises as uid
temperature increases, so it is important to ensure
the transmission temperature is within range.
1. Locate the transmission dipstick at the rear of
the engine compartment, on the passenger’s
side of the vehicle.
The dipstick handle has
this graphic. SeeEngine
Compartment Overview
on page 430for
more information.
2. Flip the handle up, and then pull out the
dipstick and wipe it with a clean rag or
paper towel.
443

Notice:If your engine catches re because
you keep driving with no coolant, your vehicle
can be badly damaged. The costly repairs
would not be covered by your warranty.
SeeOverheated Engine Protection Operating
Mode on page 450for information on driving
to a safe place in an emergency.
If No Steam Is Coming From Your
Engine
The ENGINE OVERHEATED STOP ENGINE
or the ENGINE OVERHEATED IDLE ENGINE
message, along with a low coolant condition,
can indicate a serious problem.
If you get an engine overheat warning, but see or
hear no steam, the problem may not be too
serious. Sometimes the engine can get a little too
hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. SeeTowing a Trailer
on page 400.If you get the ENGINE OVERHEATED STOP
ENGINE or the ENGINE OVERHEATED IDLE
ENGINE message with no sign of steam, try this
for a minute or so:
1. If you have an air conditioner and it is on,
turn it off.
2. Turn on your heater to full hot at the highest
fan speed and open the windows as
necessary.
3. In heavy traffic, let the engine idle in
NEUTRAL (N) while stopped. If it is safe to
do so, pull off the road, shift to PARK (P)
or NEUTRAL (N) and let the engine idle.
If you no longer have the overheat warning,
you can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not
come back on, you can drive normally.
If the warning continues, pull over, stop, and
park your vehicle immediately.
449

If there is still no sign of steam and your vehicle
is equipped with an engine-driven cooling fan,
push down the accelerator until the engine speed
is about twice as fast as normal idle speed for
at least ve minutes while you are parked.
If there is still no sign of steam and your vehicle is
equipped with an electric cooling fan, idle the
engine for ve minutes while you are parked.
If you still have the warning, turn off the engine
and get everyone out of the vehicle until it
cools down. Also, see “Overheated Engine
Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get
service help right away.Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is
displayed, an overheat protection mode which
alternates ring groups of cylinders helps prevent
engine damage. In this mode, you will notice a
loss in power and engine performance. This
operating mode allows your vehicle to be driven to
a safe place in an emergency. Driving extended
miles (km) and/or towing a trailer in the overheat
protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine
damage, allow the engine to cool before
attempting any repair. The engine oil will be
severely degraded. Repair the cause of coolant
loss, change the oil and reset the oil life
system. SeeEngine Oil on page 432.
450

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. Then 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 ll procedure steps 1 through 6.
Engine Fan Noise
Your vehicle has electric cooling fans, you may
hear the fans spinning at low speed during
most everyday driving. The fans may turn off if no
cooling is required. Under heavy vehicle loading,
trailer towing, and/or high outside temperatures, or
if you are operating your air conditioning system,
the fans may change to high speed and you
may hear an increase in fan noise. This is normal
and indicates that the cooling system is
functioning properly. The fans will change to low
speed when additional cooling is no longer
required.
456

Vehicles that have the Tire Pressure Monitor
System (TPMS) will need to have the TPMS
sensors reset after a tire rotation. See “TPMS
Sensor Identication Codes” underTire Pressure
Monitor System on page 490.
Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specications on page 546.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a 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.
SeeChanging a Flat Tire on page 506.
When It Is Time for New Tires
One way to tell when it
is time for new tires is
to check the treadwear
indicators, which will
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.
You need a new tire if any of the following
statements are true:
You can see the indicators at three or more
places around the tire.
You can see cord or fabric showing through
the tire’s rubber.
The tread or sidewall is cracked, cut or
snagged deep enough to show cord or fabric.
The tire has a bump, bulge, or split.
The tire has a puncture, cut, or other damage
that cannot be repaired well because of the
size or location of the damage.
497

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.
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.{CAUTION:
Lifting a vehicle and getting under it to
do maintenance or repairs is dangerous
without the appropriate safety equipment
and training. The jack provided with your
vehicle is designed only for changing a
at tire. If it is used for anything else, you
or others could be badly injured or killed
if the vehicle slips off the jack. Use the
jack provided with your vehicle only for
changing a at tire.
If a tire goes at, the next part shows how to use the
jacking equipment to change a at tire safely.
505

To access the spare tire, refer to the following
graphics and instructions:
A. Hoist Assembly
B. Hoist Shaft
C. Hoist Shaft Access
Cover/HoleD. Jack Handle
Extensions
E. Wheel Wrench
F. Hoist CableG. Tire Retainer
H. Spare Tire (Valve
Stem Pointed Down)
I. Hoist Shaft
Access HoleJ. Hoist End of
Extension Tool
K. Spare Tire Lock
1. To reach the hoist shaft access cover (C),
you will rst need to remove the hitch cover.
Remove it by turning the two fasteners located
at the bottom of the cover counterclockwise
and then pull the cover down and rotate
towards you.
2. Remove the hoist shaft access cover (C) on
the bumper to access the spare tire lock (K).
509

5. Insert the open end
of the extension (J)
through the hole
in the rear
bumper (I) (hoist
shaft access hole).
Be sure the hoist end (J) of the extension (D)
connects to the hoist shaft (B). The ribbed
square end of the extension is used to lower
the spare tire.
6. Turn the wheel wrench (E) counterclockwise
to lower the spare tire (H) to the ground.
Continue to turn the wheel wrench until the
spare tire can be pulled out from under
the vehicle.
If the spare tire does not lower to the ground,
the secondary latch is engaged causing
the tire not to lower. SeeSecondary Latch
System on page 518for more information.7. Use the wheel
wrench hook that
allows you to
pull the hoist cable
towards you, to
assist in reaching
the spare tire.
8. Tilt the tire
retainer (G) at the
end of the cable
when the tire
has been lowered,
so it can be
pulled up through
the wheel opening.
9. Put the spare tire near the at tire.
511

{CAUTION:
Rust or dirt on the wheel, or on the parts
to which it is fastened, can make the
wheel nuts become loose after a time.
The wheel could come off and cause an
accident. When you change a wheel,
remove any rust or dirt from the 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.
6. Remove any rust or
dirt from the wheel
bolts, mounting
surfaces and spare
wheel.
{CAUTION:
Never use oil or grease on studs or nuts.
If you do, the nuts might come loose.
Your wheel could fall off, causing a
serious accident.
7. Put the wheel nuts back on with the rounded
end of the nuts toward the wheel after
mounting the spare tire.
8. Tighten each wheel nut by hand. Then use
the wheel wrench to tighten the nuts until the
wheel is held against the hub.
9. Turn the wheel wrench counterclockwise to
lower the vehicle. Lower the jack completely.
516

4. Repeat this procedure at least two times.
If the spare tire lowers to the ground,
continue with Step 5 ofRemoving the
Spare Tire and Tools on page 507.
5. If the spare tire does not lower, turn the wheel
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 bottom
edge of the jack (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.
519