2010 GMC YUKON DENALI tow

Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the transmission
fluid level. The only reason for fluid loss is a
transmission leak or overheating the transmission.
If you suspect a small leak, then use the following
checking procedures to check the fluid level. However,
if there is a large leak, then it may be necessary to have
the vehicle towed to a dealer/retailer service department
and have it repaired before driving the vehicle further.
Notice:Use of the incorrect automatic transmission
fluid may damage the vehicle, and the damages may
not be covered by the vehicle's warranty. Always
use the automatic transmission fluid listed in
Recommended Fluids and Lubricants on page 7‑11.
Change the fluid and filter at the intervals listed in the
Maintenance Schedule. See Scheduled Maintenance
on page 7‑3. Be sure to use the transmission fluid
listed in Recommended Fluids and Lubricantson
page 7‑11.
How to Check Automatic Transmission
Fluid
Notice: Too much or too little fluid can damage your
transmission. Too much can mean that some of the
fluid could come out and fall on hot engine parts or
exhaust system parts, starting a fire. Too little fluid
could cause the transmission to overheat. Be sure
to get an accurate reading if you check your
transmission fluid.
Before checking the fluid level, prepare the vehicle as
follows:
1. Start the engine and park the vehicle on a level surface. Keep the engine running.
2. Apply the parking brake and place the shift lever in P (Park).
3. With your foot on the brake pedal, move the shift lever through each gear range, pausing for about
three seconds in each range. Then, move the shift
lever back to P (Park).
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4. Allow the engine to idle (500–800 rpm) for at least
one minute. Slowly release the brake pedal.
5. Keep the engine running and press the Trip/Fuel button or trip odometer reset stem until TRANS
TEMP (Transmission Temperature) displays on the
Driver Information Center (DIC).
6. Using the TRANS TEMP reading, determine and perform the appropriate check procedure. If the
TRANS TEMP reading is not within the required
temperature ranges, allow the vehicle to cool,
or operate the vehicle until the appropriate
transmission fluid temperature is reached.
Cold Check Procedure
Use this procedure only as a reference to determine
if the transmission has enough fluid to be operated
safely until a hot check procedure can be made.
The hot check procedure is the most accurate
method to check the fluid level. Perform the hot
check procedure at the first opportunity. Use this cold check procedure to check fluid level when
the transmission temperature is between 80°F and 90°F
(27°C and 32°C).
1. Locate the
transmission dipstick at
the rear of the engine
compartment, on the
passenger side of the
vehicle.
See Engine Compartment Overview
on page 6‑14for 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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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 one pint (0.5L). Do not
overfill.
6. Perform a hot check at the first opportunity after the transmission reaches a normal
operating temperature between 160°F to 200°F
(71°C to 93°C).
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
160°F and 200°F (71°C and 93°C).
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 6‑14for 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.
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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 5‑42. 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 gage 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 6‑15.
Engine Fan Noise
The vehicle has electric cooling fans. You might hear
the fans spinning at low speed during most everyday
driving. The fans can 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 can change to high
speed and you might hear an increase in fan noise.
This is normal and indicates that the cooling system is
functioning properly. The fans change to low speed
when additional cooling is no longer required.
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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 inflation pressures as shown on the Tire
and Loading Information label. SeeInflation - Tire
Pressure
on page 6‑64and Loading the Vehicleon
page 5‑31
.
Reset the Tire Pressure Monitor System. See Tire
Pressure Monitor Operation
on page 6‑68. Make certain that all wheel nuts are properly
tightened. See
“Wheel Nut Torque” under
Capacities and Specifications
on page 6‑115.
{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 6‑80.
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 6‑94.
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WARNING: (Continued)
crash. Use another type of traction device only if
its manufacturer recommends it for use on the
vehicle and tire size combination and road
conditions. Follow that manufacturer's
instructions. To help avoid damage to the vehicle,
drive slowly, re‐adjust or remove the device if it is
contacting the vehicle, and do not spin the
wheels. If you do find traction devices that will fit,
install them on the rear tires.
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.
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To access the spare tire:
A. Hoist Assembly
B. Hoist Shaft
C. Hoist Shaft Access Cover/Hole
D. Jack Handle Extensions
E. Wheel Wrench F. Hoist Cable G. Tire/Wheel Retainer
H. Spare Tire (Valve Stem Pointed Down)
I. Hoist Shaft Access Hole
J. Hoist End of Extension Tool
K. Spare Tire Lock 1. To reach the hoist shaft access cover (C), you will
first 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).
3. To remove the spare tire lock, insert the ignitionkey, turn it clockwise and then pull straight back.
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