2010 HUMMER H3 automatic transmission

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.

9-74 Driving and Operating
Leaving After Parking on a Hill
1. Apply and hold the brake pedalwhile you:
.start the engine,
.shift into a gear, and
.release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See this
manual's Maintenance Schedule
or Index for more information.
Things that are especially important
in trailer operation are automatic
transmission fluid, engine oil, axle lubricant, belts, cooling system and
brake system. It is a good idea to
inspect these before and during
the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See
Engine Overheating
on page 10‑22.
Trailer Towing
Three important considerations
have to do with weight:
.The weight of the trailer.
.The weight of the trailer tongue.
.The total weight on the vehicle's
tires.
Weight of the Trailer
How heavy can a trailer safely be?
Speed, altitude, road grades,
outside temperature, special
equipment, and the amount of
tongue weight the vehicle can carry
must be considered. See “Weight of
the Trailer Tongue” later in this
section for more information.
Maximum trailer weight is calculated
assuming only the driver is in the
tow vehicle and it has all the
required trailering equipment.
The weight of additional optional
equipment, passengers and cargo in
the tow vehicle must be subtracted
from the maximum trailer weight.
Use the following chart to determine
how much a vehicle can weigh,
based on the vehicle model and
options.

Driving and Operating 9-75
VehicleAxle Ratio Maximum Trailer Weight *GCWR
H3 3.7L L5 Engine, Automatic
Transmission 4.56
4,500 lbs (2 041 kg) 9,500 lbs (4 309 kg)
3.7L L5 Engine, Manual
Transmission 4.56
3,000 lbs (1 361 kg) 8,000 lbs (3 629 kg)
5.3L V8 Engine, Automatic
Transmission 4.10
6,000 lbs (2 721 kg) 11,400 lbs (5 171 kg)
H3T 3.7L L5 Engine, Automatic
Transmission 4.56
4,400 lbs (1 996 kg) 9,500 lbs (4 309 kg)
3.7L L5 Engine, Manual
Transmission 4.56
2,900 lbs (1 315 kg) 8,000 lbs (3 629 kg)
5.3L V8 Engine, Automatic
Transmission 4.10
5,900 lbs (2 676 kg) 11,400 lbs (5 171 kg)
*The Gross Combination Weight Rating (GCWR) in the total allowable weight of the completely loaded vehicle and
trailer including any passengers, cargo, equipment and conversions. The GCWR for the vehicle should not be
exceeded.

Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . 10-2
California Perchlorate Materials Requirements . . . . 10-3
Accessories and Modifications . . . . . . . . . . . . . . . 10-3
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 10-4
Hood . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 10-6
Engine Oil . . . . . . . . . . . . . . . . . . . 10-9
Engine Oil Life System . . . . . 10-11
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 10-12
Manual Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 10-15 Hydraulic Clutch . . . . . . . . . . . . 10-16
Engine Air Cleaner/Filter . . . . 10-17
Cooling System . . . . . . . . . . . . 10-18
Engine Coolant . . . . . . . . . . . . . 10-19
Engine Overheating . . . . . . . . 10-22
Engine Fan . . . . . . . . . . . . . . . . . 10-24
Power Steering Fluid . . . . . . . 10-24
Washer Fluid . . . . . . . . . . . . . . . 10-25
Brakes . . . . . . . . . . . . . . . . . . . . . 10-26
Brake Fluid . . . . . . . . . . . . . . . . . 10-27
Battery . . . . . . . . . . . . . . . . . . . . . 10-28
Four-Wheel Drive . . . . . . . . . . . 10-29
Front Axle . . . . . . . . . . . . . . . . . . 10-29
Rear Axle . . . . . . . . . . . . . . . . . . 10-29
Starter Switch Check . . . . . . . 10-30
Automatic Transmission Shift
Lock Control System
Check . . . . . . . . . . . . . . . . . . . . . 10-30
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . 10-31
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-31
Wiper Blade Replacement . . . . . . . . . . . . . . 10-32
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . 10-33
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-35
Halogen Bulbs . . . . . . . . . . . . . . 10-35
Headlamps . . . . . . . . . . . . . . . . . 10-35
Taillamps, Turn Signal,Stoplamps, and Back-Up
Lamps (H3) . . . . . . . . . . . . . . . 10-35
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps (H3T) . . . . . . . . . . . . . . 10-36
License Plate Lamp . . . . . . . . 10-37
Replacement Bulbs . . . . . . . . . 10-37
Electrical System
Electrical System Overload . . . . . . . . . . . . . . . . . . 10-38
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-39
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-39

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.

10-12 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.

10-14 Vehicle Care
Then, without shutting off the
engine:
1. Flip the handle up and then pullout the dipstick and wipe it with
a clean rag or paper towel.
The automatic transmission
dipstick handle with this symbol
on it is located in the engine
compartment on the passenger
side of the vehicle.
See Engine Compartment
Overview
on page 10‑6for
more information on location.
2. Push it back in all the way, wait three seconds, and pull it back
out again.
3. Check both sides of the dipstick,
and read the lower level. The
fluid level must be in the COLD
area, below the cross-hatched
area, for a cold check or in the
HOT or cross-hatched area for a
hot check. Be sure to keep the
dipstick pointed down to get an
accurate reading.
4. 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.
How to Add Automatic
Transmission Fluid
Refer to the Maintenance
Schedule to determine what kind
of transmission fluid to use. See
Recommended Fluids and
Lubricants on page 11‑8.
Add fluid only after checking the
transmission fluid while it is hot.
A cold check is used only as a
reference. If the fluid level is low,
add only enough of the proper fluid
to bring the level up to the HOT area
for a hot check. It does not take
much fluid, generally less than one
pint (0.5 L). Do not overfill.