2010 GMC YUKON tow

5. If the fluid level is below the COLD check band,add only enough fluid as necessary to bring the
level into the COLD band. It does not take much
fluid, generally less than 0.5 Liter (1 Pint). Do not
overfill.
6. Perform a hot check at the first opportunity after the transmission reaches a normal
operating temperature between 71°C to 93°C
(160°F to 200°F).
7. If the fluid level is in the acceptable range, push the dipstick back in all the way, then flip the handle
down to lock the dipstick in place.
Hot Check Procedure
Use this procedure to check the transmission fluid level
when the transmission fluid temperature is between
71°C and 93°C (160°F and 200°F).
The hot check is the most accurate method to check
the fluid level. The hot check should be performed at
the first opportunity in order to verify the cold check.
The fluid level rises as fluid temperature increases,
so it is important to ensure the transmission
temperature is within range.
1. Locate thetransmission dipstick at
the rear of the engine
compartment, on the
passenger side of the
vehicle.
See Engine Compartment Overview
on page 6‑16for more information.
2. Flip the handle up, and then pull out the dipstick and wipe it with a clean rag or paper towel.
3. Install the dipstick by pushing it back in all the way, wait three seconds, and then pull it back out again.
4. Check both sides of the dipstick and read the lower level. Repeat the check procedure to verify the
reading.
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If No Steam Is Coming From The
Engine Compartment
The ENGINE OVERHEATED STOP ENGINE or the
ENGINE OVERHEATED IDLE ENGINE message, along
with a low coolant condition, can indicate a serious
problem.
If an engine overheat warning is displayed but no steam
can be seen or heard, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer. SeeTowing a Trailer on page 5‑49.
If the overheat warning is displayed with no sign of
steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest fan speed. Open the windows as
necessary. 3. In heavy traffic, let the engine idle in N (Neutral)
while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let the
engine idle.
If the temperature overheat gauge is no longer in
the overheat zone or an overheat warning no longer
displays, the vehicle can be driven. Continue to drive
the vehicle slow for about 10 minutes. Keep a safe
vehicle distance from the car in front of you. If the
warning does not come back on, continue to drive
normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for
three minutes while parked. If the warning is still
displayed, turn off the engine until it cools down.
Also, see “Overheated Engine Protection Operating
Mode” later in this section.
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Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
ENGINE POWER IS REDUCED message is displayed,
an overheat protection mode which alternates firing
groups of cylinders helps prevent engine damage.
In this mode, you will notice a loss in power and engine
performance. This operating mode allows the 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. See Engine Oil
on
page 6‑18.
Engine Fan Noise
If the vehicle has a clutched engine cooling fan, when
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the fan is spinning slower and the clutch is
not fully engaged. This improves fuel economy and
reduces fan noise. Under heavy vehicle loading, trailer
towing, and/or high outside temperatures, the fan speed
increases as the clutch more fully engages, so you may
hear an increase in fan noise. This is normal and should
not be mistaken as the transmission slipping or making
extra shifts. It is merely the cooling system functioning
properly. The fan will slow down when additional cooling
is not required and the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
If the 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 the 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.
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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.
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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

4. Insert the open endof 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. 5. 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. See Secondary Latch System
on page 6‑100for more information.
6. Use the wheel wrench
hook that allows you
to pull the hoist cable
towards you, to assist
in reaching the
spare tire.
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7. Tilt the tire toward the vehicle with some slackin the cable to access the tire/wheel retainer.
Separate the retainer from the guide pin by sliding
the retainer up the pin while pressing down on the
latch.
Once the retainer is separated from the guide pin,
tilt the retainer and pull it through the center of the
wheel along with the cable and latch.
8. Put the spare tire near the flat tire.
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5. Remove all of thewheel nuts.
6. Take off the flat tire.
7. Remove any rust or dirt from the wheel bolts,
mounting surfaces,
and spare wheel.
{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 changing a wheel, remove any
rust or dirt from places where the wheel attaches
to the vehicle. In an emergency, 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
.
8. Put the wheel nuts back on with the rounded end of the nuts toward the wheel after mounting the
spare tire.
{WARNING:
Never use oil or grease on bolts or nuts because
the nuts might come loose. The vehicle's wheel
could fall off, causing a crash.
6-98