2010 GMC ACADIA automatic transmission

9-46 Driving and Operating
Tow/Haul Mode
Tow/Haul assists when pulling a
heavy trailer or a large or heavy
load. The purpose of the Tow/Haul
mode is to:
.Reduce the frequency and
improve the predictability of
transmission shifts.
.Provide the same solid shift feel
as when the vehicle is unloaded.
.Improve control of vehicle speed
while requiring less throttle pedal
activity.
.Increase the charging system
voltage to assist in recharging a
battery installed in a trailer.
Press this button located on the
console to turn on and turn off the
Tow/Haul mode.
The Tow/Haul light on the
instrument panel comes on to
indicate that Tow/Haul mode has
been selected.
Tow/Haul may be turned off by
pressing the button again, at which
time the indicator light on the
instrument panel will turn off. The
vehicle will automatically turn off
Tow/Haul every time it is started.Tow/Haul is designed to be most
effective when the vehicle and
trailer combined weight is at least
75 percent of the vehicle's Gross
Combined Weight Rating (GCWR).
See
Trailer Towing
on page 9‑49.
Tow/Haul is most useful when
pulling a heavy trailer or a large or
heavy load under the following
driving conditions:
.Travelling through rolling terrain.
.Travelling in stop and go traffic.
.Travelling in busy parking lots
where improved low speed
control of the vehicle is desired.
Operating the vehicle in Tow/Haul
when lightly loaded or with no trailer
will not cause damage but there is
no benefit. Such a selection when
unloaded may result in unpleasant
engine and transmission driving
characteristics and reduced fuel
economy.

Driving and Operating 9-49
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. 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. SeeEngine Overheating
on page 10‑19.
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.

Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-3
California Proposition 65Warning . . . . . . . . . . . . . . . . . . . . 10-3
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 Cover . . . . . . . . . . . . . . . . 10-7 Engine Oil . . . . . . . . . . . . . . . . . . . 10-8
Engine Oil Life System . . . . . 10-10
Automatic Transmission
Fluid . . . . . . . . . . . . . . . . . . . . . . 10-11
Engine Air Cleaner/Filter . . . . 10-12
Cooling System . . . . . . . . . . . . 10-14
Engine Coolant . . . . . . . . . . . . . 10-14
Engine Overheating . . . . . . . . 10-19
Overheated Engine
Protection
Operating Mode . . . . . . . . . . . 10-21
Power Steering Fluid . . . . . . . 10-21
Washer Fluid . . . . . . . . . . . . . . . 10-22
Brakes . . . . . . . . . . . . . . . . . . . . . 10-23
Brake Fluid . . . . . . . . . . . . . . . . . 10-24
Battery . . . . . . . . . . . . . . . . . . . . . 10-25
All-Wheel Drive . . . . . . . . . . . . . 10-26
Starter Switch Check . . . . . . . 10-26
Automatic Transmission Shift Lock Control System
Check . . . . . . . . . . . . . . . . . . . . . 10-26 Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . 10-27
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-27
Wiper Blade
Replacement . . . . . . . . . . . . . . 10-27
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . 10-28
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-29
Halogen Bulbs . . . . . . . . . . . . . . 10-29
License Plate Lamp . . . . . . . . 10-29
Replacement Bulbs . . . . . . . . . 10-29
Electrical System
High Voltage Devices andWiring . . . . . . . . . . . . . . . . . . . . . 10-30
Electrical System Overload . . . . . . . . . . . . . . . . . . 10-30

Vehicle Care 10-7
A. Radiator Pressure Cap . SeeCooling System on page 10‑14.
B. Engine Coolant Recovery Cap. See Cooling System
on
page 10‑14.
C. Remote Negative (−) Terminal. See Jump Starting
on
page 10‑78.
D. Engine Compartment Fuse
Block on page 10‑31.
E. Remote Positive (+) Terminal. See Jump Starting
on
page 10‑78.
F. Power Steering Reservoir and Cap (under engine cover). See
Power Steering Fluid
on
page 10‑21.
G. Engine Oil Fill Cap. See “When
to Add Engine Oil” underEngine
Oil on page 10‑8. H.
Engine Cover on page 10‑7.
I. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil on page 10‑8.
J. Automatic Transmission Fluid Dipstick. See “Checking the
Fluid Level” underAutomatic
Transmission Fluid
on
page 10‑11.
K. Brake Master Cylinder Reservoir. See “Brake Fluid”
under Brakes on page 10‑23.
L. Engine Air Cleaner/Filter
on
page 10‑12.
M. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid
on
page 10‑22.
Engine Cover
A. Oil Fill Cap
B. Engine Cover
To remove:
1. Remove the oil fill cap (A).
2. Raise the engine cover (B) to release from the retainers.
3. Lift and remove the engine cover.
4. Reverse Steps 1 through 3 to reinstall engine cover.

Vehicle Care 10-11
2. Press and hold the trip odometerreset stem until OIL LIFE
REMAINING shows 100%.
Three chimes sound and the
CHANGE ENGINE OIL SOON
message goes off.
3. Turn the key to LOCK/OFF. If the CHANGE ENGINE OIL
SOON message comes back on
when the vehicle is started, the
engine oil life system has not
reset. Repeat the procedure.
If the vehicle has Driver Information
Center (DIC) buttons:
1. Turn the ignition to ON/RUN, with the engine off.
2. Press the vehicle information button until OIL LIFE
REMAINING displays. 3. Press and hold the set/reset
button until 100% is displayed.
Three chimes sound and the
CHANGE ENGINE OIL SOON
message goes off.
4. Turn the key to LOCK/OFF.
If the CHANGE ENGINE OIL SOON
message comes back on when the
vehicle is started, the engine oil life
system has not reset. Repeat the
procedure.
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
It is not necessary to check the
transmission fluid level.
A transmission fluid leak is the only
reason for fluid loss. If a leak
occurs, take the vehicle to the
dealer/retailer and have it repaired
as soon as possible.

10-12 Vehicle Care
Change the fluid at the intervals
listed inScheduled Maintenanceon
page 11‑2, and be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants on page 11‑8.
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.
The transmission fluid will not reach
the end of the dipstick unless the
transmission is at operating
temperature. If you need to check
the transmission fluid level, please
take the vehicle to your dealer/
retailer.
Engine Air Cleaner/Filter
When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/filter at the
Maintenance IIintervals and replace
it at the first oil change after each
80 000 km (50,000 mile) interval.
See Scheduled Maintenance
on
page 11‑2for more information.
If driving in dusty/dirty conditions,
inspect the filter at each engine oil
change.
See Engine Compartment Overview
on page 10‑6for the location of the
engine air cleaner/filter.
How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/filter,
remove the filter from the vehicle
and lightly shake the filter (away
from vehicle) to release loose dust
and dirt. If the filter remains caked
with dirt, a new filter is required. To inspect or replace the engine air
cleaner/filter, do the following:
1. Remove the engine cover. See
Engine Cover on page 10‑7.
A. Ventilation Tube
B. Sensor
2. Disconnect the cover fitting from the ventilation tube (A).
3. Disconnect the wiring harness connector from the sensor (B).

10-26 Vehicle Care
All-Wheel Drive
It is not necessary to check the
all–wheel drive lubricant levels.
A fluid leak is the only reason for
fluid loss. If a leak occurs, take the
vehicle to the dealer/retailer as soon
as possible.
Starter Switch Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular brake.
See Parking Brake
on
page 9‑27. Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer/
retailer for service.
Automatic Transmission
Shift Lock Control
System Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured. 1. Before starting this check, be
sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Firmly apply the parking brake. See Parking Brake
on
page 9‑27.
Be ready to apply the regular
brake immediately if the vehicle
begins to move.
3. With the engine off, turn the ignition to ON/RUN, but do not
start the engine. Without
applying the regular brake, try to
move the shift lever out of
P (Park) with normal effort. If the
shift lever moves out of P (Park),
contact your dealer/retailer for
service.

10-40 Vehicle Care
(C) Aspect Ratio:A two-digit
number that indicates the tire
height-to-width measurements.
For example, if the tire size
aspect ratio is 60, as shown in
item C of the illustration, it would
mean that the tire's sidewall is
60 percent as high as it is wide.
(D) Construction Code
:A
letter code is used to indicate
the type of ply construction in
the tire. The letter R means
radial ply construction; the
letter D means diagonal or bias
ply construction; and the letter B
means belted-bias ply
construction.
(E) Rim Diameter
:Diameter of
the wheel in inches.
(F) Service Description
:These
characters represent the load
index and speed rating of the
tire. The load index represents
the load carry capacity a tire is certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch of
the tire. Air pressure is
expressed in psi (pounds per
square inch) or kPa (kilopascal).
Accessory Weight
:This
means the combined weight of
optional accessories. Some
examples of optional
accessories are, automatic
transmission, power steering,
power brakes, power windows,
power seats, and air
conditioning.
Aspect Ratio
:The relationship
of a tire's height to its width. Belt
:A rubber coated layer of
cords that is located between
the plies and the tread. Cords
may be made from steel or other
reinforcing materials.
Bead
:The tire bead contains
steel wires wrapped by steel
cords that hold the tire onto
the rim.
Bias Ply Tire
:A pneumatic tire
in which the plies are laid at
alternate angles less than
90 degrees to the centerline of
the tread.
Cold Tire Pressure
:The
amount of air pressure in a tire,
measured in psi (pounds per
square inch) or kPa (kilopascal)
before a tire has built up heat
from driving. See Tire Pressure
on page 10‑43.