Driving and Operating 9-73
Vehicles with an automatic
transmission can tow in D (Drive).
Shift the transmission to a lower
gear if the transmission shifts too
often under heavy loads and/or
hilly conditions. For vehicles with a
manual transmission, it is better not
to use the highest gear.
When towing at high altitude on
steep uphill grades, consider the
following: Engine coolant will boil at
a lower temperature than at normal
altitudes. If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the
vehicle may show signs similar to
engine overheating. To avoid this,
let the engine run while parked,
preferably on level ground, with the
automatic transmission in P (Park)
for a few minutes before turning the
engine off. For vehicles with manualtransmissions, let the engine run
while parked, preferably on level
ground, with the transmission out of
gear and the parking brake applied,
for a few minutes before turning the
engine off. If the overheat warning
comes on, see
Engine Overheating
on page 10‑22.
Parking on Hills
{WARNING
Parking the vehicle on a hill
with the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface. If parking the rig on a hill:
1. Press the brake pedal, but do
not shift into P (Park) yet for
vehicles with an automatic
transmission, or into gear
for vehicles with a manual
transmission. Turn the wheels
into the curb if facing downhill
or into traffic if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the brake pedal
until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake and shift
into P (Park) for vehicles with an
automatic transmission or into
gear for vehicles with a manual
transmission.
5. Release the brake pedal.
Vehicle Care 10-7
A. Windshield Washer FluidReservoir. See “Adding Washer
Fluid” under Washer Fluid
on
page 10‑25.
B. Engine Coolant Recovery Tank. See Engine Coolant
on
page 10‑19.
C. Engine Air Cleaner/Filter
on
page 10‑17.
D. Power Steering Fluid Reservoir. See Power Steering Fluid
on
page 10‑24.
E. Automatic Transmission Fluid Dipstick (If Equipped). See
“Checking the Fluid Level” under
Automatic Transmission Fluid
on
page 10‑12.
F. Engine Oil Fill Cap. See “When
to Add Engine Oil” underEngine
Oil on page 10‑9. G. Radiator Pressure Cap. See
Cooling System on page 10‑18.
H. Remote Negative (−) Terminal (GND). See Jump Starting
on
page 10‑86.
I. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil on page 10‑9.
J. Positive (+) Battery Terminal. See Jump Starting
on
page 10‑86.
K. Brake Fluid Reservoir. See “Brake Fluid” under
Brakes on page 10‑26.
L. Engine Compartment Fuse
Block on page 10‑39.
M. Battery on page 10‑28.
N. Hydraulic Clutch Fluid Reservoir (If Equipped). See Hydraulic
Clutch on page 10‑16.
Vehicle Care 10-9
A.Engine Air Cleaner/Filteron
page 10‑17.
B. Air Filter Restriction Indicator (If Equipped). See Engine Air
Cleaner/Filter
on page 10‑17.
C. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid
on
page 10‑25.
D. Engine Coolant Recovery Tank. See Engine Coolant
on
page 10‑19.
E. Automatic Transmission Fluid Dipstick (If Equipped). See
“Checking the Fluid Level” under
Automatic Transmission Fluid
on
page 10‑12. F. Engine Oil Dipstick. See
“Checking Engine Oil” under
Engine Oil on page 10‑9.
G. Engine Oil Fill Cap. See “When
to Add Engine Oil” underEngine
Oil on page 10‑9.
H. Brake Fluid Reservoir. See “Brake Fluid” underBrakes
on
page 10‑26.
I. Battery on page 10‑28.
J. Power Steering Fluid Reservoir. See Power Steering Fluid
on
page 10‑24.
K. Engine Compartment Fuse
Block on page 10‑39.
L. Radiator Pressure Cap. See Cooling System on page 10‑18.
Engine Oil
Checking Engine Oil
It is a good idea to check the engine
oil level at each fuel fill. In order to
get an accurate reading, the oil
must be warm and the vehicle must
be on level ground.
The engine oil dipstick handle
is a yellow loop. See Engine
Compartment Overview
on
page 10‑6for the location of the
engine oil dipstick.
1. Turn off the engine and give the oil several minutes to drain back
into the oil pan. If this is not
done, the oil dipstick might not
show the actual level.
2. Pull out the dipstick and clean it with a paper towel or cloth,
then push it back in all the way.
Remove it again, keeping the tip
down, and check the level.
10-10 Vehicle Care
When to Add Engine Oil
If the oil is below the cross-hatched
area (L), add at least one liter/quart
of the recommended oil. This
section explains what kind of oil to
use. For engine oil crankcase
capacity, seeCapacities and
Specifications on page 12‑2.
Notice: Do not add too much oil.
If the engine has so much oil
that the oil level gets above the
cross-hatched area that shows
the proper operating range, the
engine could be damaged.
See Engine Compartment Overviewon page 10‑6for the location of the
engine oil fill cap.
Add enough oil to put the level
somewhere in the proper operating
range. Push the dipstick all the way
back in when through.
What Kind of Engine Oil to Use
Look for three things:
.GM6094M
Use only an oil that meets
GM Standard GM6094M.
.SAE 5W-30
SAE 5W-30 is best for the
vehicle. These numbers on
an oil container show its
viscosity, or thickness. Do not
use other viscosity oils such
as SAE 20W-50.
.American Petroleum Institute
(API) starburst symbol
Oils meeting these requirements
should have the starburst
symbol on the container. This
symbol indicates that the oil has
been certified by the American
Petroleum Institute (API).
Notice: Use only engine oil
identified as meeting GM
Standard GM6094M and showing
the American Petroleum Institute
Certified For Gasoline Engines
starburst symbol. Failure to use
the recommended oil can result
in engine damage not covered by
the vehicle warranty.
Vehicle Care 10-11
Cold Temperature Operation
If in an area of extreme cold, where
the temperature falls below−29°C
(−20°F), use either an SAE 5W-30
synthetic oil or an SAE 0W-30
engine oil. Both provide easier
cold starting for the engine at
extremely low temperatures. Always
use an oil that meets the required
specification, GM6094M. See “What
Kind of Engine Oil to Use” for more
information.
Engine Oil Additives / Engine
Oil Flushes
Do not add anything to the oil.
The recommended oils with the
starburst symbol that meet GM
standards are all that is needed
for good performance and engine
protection.
Engine oil system flushes are not
recommended and could cause
engine damage not covered by the
vehicle warranty.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system
that indicates when to change the
engine oil and filter. This is based
on engine revolutions and engine
temperature, and not on mileage.
Based on driving conditions, the
mileage at which an oil change is
indicated can vary considerably. For
the oil life system to work properly,
the system must be reset every time
the oil is changed.
When the system has calculated
that oil life has been diminished,
it indicates that an oil change
is necessary. A “Change Oil”
message comes on. See Engine Oil
Messages
on page 5‑23. Change
the oil as soon as possible within
the next 1 000 km (600 miles). It is
possible that, if driving under the
best conditions, the oil life system
might not indicate that an oil change
is necessary for over a year. However, the engine oil and filter
must be changed at least once a
year and at this time the system
must be reset. Your dealer has
trained service people who will
perform this work using genuine
parts and reset the system. It is also
important to check the oil regularly
and keep it at the proper level.
If the system is ever reset
accidentally, the oil must be
changed at 5 000 km (3,000 miles)
since the last oil change.
Remember to reset the oil life
system whenever the oil is changed.
How to Reset the Engine Oil
Life System
The Engine Oil Life System
calculates when to change the
engine oil and filter based on
vehicle use. Whenever the oil is
changed, reset the system so it can
calculate when the next oil change
is required. If a situation occurs
where the oil is changed prior to a
change engine oil message being
turned on, reset the system.
10-12 Vehicle Care
After changing the engine oil, reset
the system:
1. Turn the ignition key to ON/RUNwith the engine off.
2. Press and release the stem in the lower center of the
instrument cluster until the OIL
LIFE message is displayed.
3. Once the alternating “Oil Life”
and “Reset” messages appear,
press and hold the stem until
several beeps sound. This
confirms that the oil life system
has been reset.
4. Turn the key to LOCK/OFF.
If the “Change Oil” message
comes on again and stays on for
30 seconds at the next ignition
cycle, it did not reset. The system
needs to be reset again.What to Do with Used Oil
Used engine oil contains certain
elements that can be unhealthy for
your skin and could even cause
cancer. Do not let used oil stay on
your skin for very long. Clean your
skin and nails with soap and water,
or a good hand cleaner. Wash or
properly dispose of clothing or rags
containing used engine oil. See the
manufacturer's warnings about the
use and disposal of oil products.
Used oil can be a threat to the
environment. If you change your
own oil, be sure to drain all the oil
from the filter before disposal. Never
dispose of oil by putting it in the
trash, pouring it on the ground, into
sewers, or into streams or bodies of
water. Recycle it by taking it to a
place that collects used oil.
Automatic Transmission
Fluid
When to Check and Change
Automatic Transmission Fluid
A good time to check the automatic
transmission fluid level is when the
engine oil is changed.
Change the fluid and filter at the
intervals listed in Scheduled
Maintenance
on page 11‑2, and be
sure to use the transmission fluid
listed in Recommended Fluids and
Lubricants on page 11‑8.
How to Check Automatic
Transmission Fluid
Because this operation can be a
little difficult, you may choose to
have this done at the dealer service
department.
If adding it yourself, be sure to
follow all the instructions here,
or there could be a false reading on
the dipstick.
Vehicle Care 10-15
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 11‑8.
.After adding fluid, recheck the
fluid level as described under
“How to Check Automatic
Transmission Fluid,” earlier in
this section.
.When the correct fluid level is
obtained, push the dipstick back
in all the way; then flip the
handle down to lock the dipstick
in place.
Manual Transmission
Fluid
When to Check
A good time to check the manual
transmission fluid is when the
engine oil is changed. However, the
fluid in the manual transmission
does not require changing.
How to Check
Because this operation can be a
little difficult, you may choose to
have this done at your HUMMER
dealer service department.
If doing it yourself, be sure to follow
all the instructions here, or there
could be a false reading.
Notice: Too much or too
little fluid can damage the
transmission. Too little fluid
could cause the transmission
to overheat. Be sure to get an
accurate reading if checking the
transmission fluid. To check the fluid:
1. Park the vehicle on a level
surface, then shut the engine
off. Let the vehicle sit until the
transmission case is cool
enough to touch.
2. Remove the filler plug.
3. Check that the lubricant level isup to the bottom of the filler
plug hole.
10-20 Vehicle Care
Checking Coolant
The vehicle must be on a level
surface when checking the coolant
level.
The coolant recovery tank cap has
this symbol on it.
It is located toward the rear of
the engine compartment on the
passenger side of the vehicle. See
Engine Compartment Overview
on
page 10‑6for more information on
location.
Check to see if coolant is visible in
the coolant recovery tank. If the
coolant inside the coolant recovery
tank is boiling, do not do anything
else until it cools down. If coolant is
visible but the coolant level is not at
or above the FULL COLD mark, add
a 50/50 mixture of clean, drinkable water and DEX-COOL coolant at the
coolant recovery tank, but be sure
the cooling system is cool before
this is done.
The vehicle must be on a level
surface. When the engine is cold,
the coolant level should be at FULL
COLD, or a little higher. When the
engine is warm, the level could be
above the FULL COLD level.
When the engine is cold, the coolant
level should be at least up to the
FULL COLD mark. If it is not, there
could be a leak in the cooling
system.
How to Add Coolant to the
Recovery Tank
{WARNING
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.
Notice:
This vehicle has a
specific coolant fill procedure.
Failure to follow this procedure
could cause the engine to
overheat and be severely
damaged.
When the coolant in the coolant
recovery tank is at the FULL COLD
mark, start the vehicle.
If coolant is needed, add the proper
DEX-COOL coolant mixture at the
coolant recovery tank.
How to Add Coolant to the
Radiator
{WARNING
An electric engine cooling fan
under the hood can start up even
when the engine is not running
and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.