2003 CADILLAC DEVILLE towing

Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle may need a
different turn signal ¯asher and/or extra wiring. Check
with your dealer. The arrows on your instrument
panel will ¯ash whenever you signal a turn or lane
change. Properly hooked up, the trailer lamps will also
¯ash, telling other drivers you're about to turn,
change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ¯ash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It's
important to check occasionally to be sure the trailer
bulbs are still working.
Driving on Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don't shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
On long uphill grades, reduce speed to 45 to 50 mph
(70 to 90 km/h) and avoid prolonged use of SECOND (2)
gear and engine speeds above 3800 rpm.
Climbing grades steeper than four percent at
temperatures above 90É F (32É C) with a loaded vehicle
and trailer is not recommended. The cooling system
may temporarily overheat. See
Engine Overheating on
page 5-27.
Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here's
how to do it:
1. Apply your regular brakes, but do not shift into
PARK (P).
2. Have someone place chocks behind the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then shift into PARK
(P) ®rmly and apply your parking brake.
5. Release the regular brakes.
4-39

When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
·start your engine
·shift into a gear, and
·make sure the parking brake has released.
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
Your vehicle will need service more often when you're
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transaxle ¯uid (don't over®ll),
engine oil, drive belt, cooling system and brake system.
Each of these is covered in this manual, and the
Index will help you ®nd them quickly. If you're trailering,
it's a good idea to review this information before you
start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
Your cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating on
page 5-27.
4-40

CAUTION: (Continued)
·
Be sure to use the proper nuts, bolts and
other fasteners. ªEnglishº and ªmetricº
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the air¯ow around it. This may cause wind
noise and affect windshield washer performance. Check
with your dealer before adding equipment to the
outside of your vehicle.
Fuel
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle.
Gasoline Octane
Use regular unleaded gasoline with a posted octane of
87 or higher. However, for best performance and for
trailer towing, you may wish to use middle grade
or premium unleaded gasoline. If the octane is less than
87, you may get a heavy knocking noise when you
drive. If this occurs, use a gasoline rated at 87 octane
or higher as soon as possible. Otherwise, you might
damage your engine.
5-4

Automatic Transaxle Fluid
When to Check and Change
A good time to check your automatic transaxle ¯uid
level is when the engine oil is changed.
Change both the ¯uid and ®lter every 50,000 miles
(83 000 km) if the vehicle is mainly driven under one or
more of these conditions:
·In heavy city traffic where the outside temperature
regularly reaches 90É F (32É C) or higher.
·In hilly or mountainous terrain.
·When doing frequent trailer towing.
·Uses such as found in taxi, police or delivery
service.
·Use such as limousine service.
If you do not use your vehicle under any of these
conditions, the ¯uid and ®lter do not require change until
the message CHANGE TRANS FLUID appears on
the Driver Information Center.
See
Part A: Scheduled Maintenance Services on
page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little ¯uid can damage
your transaxle. Too much can mean that some of the
¯uid could come out and fall on hot engine or
exhaust system parts, starting a ®re. Too little ¯uid
could cause the transaxle to overheat. Be sure
to get an accurate reading if you check your
transaxle ¯uid.
Wait at least 30 minutes before checking the transaxle
¯uid level if you have been driving:
·When outside temperatures are above 90É F (32É C)
·At high speed for quite a while.
·In heavy traffic ± especially in hot weather.
·While pulling a trailer.
To get the right reading, the ¯uid should be at normal
operating temperature, which is 180É F to 200É F
(82É C to 93É C).
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above
50É F (10É C). If it's colder than 50É F (10É C), you
may have to drive longer.
5-21

Adding Coolant
If you need more coolant, add the proper DEX-COOLž
coolant mixtureat the surge tank,but only when the
engine is cool.
{CAUTION:
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. Don't spill coolant on a hot engine.
When replacing the pressure cap, make sure the arrow
lines up with the tube.
Coolant Surge Tank Pressure Cap
Notice:Your pressure cap is a pressure-type
cap and must be tightly installed to prevent coolant
loss and possible engine damage from overheating.
See ªCapacities and Speci®cationsº for more
information.
Engine Overheating
You will ®nd an ENGINE COOLANT HOT, IDLE
ENGINE message or an ENGINE OVERHEATED,
STOP ENGINE message displayed in the Driver
Information Center (DIC). You will also hear a chime.
There is also an engine temperature warning light and/or
gage on the instrument panel cluster. See
Engine
Coolant Temperature Warning Light on page 3-49andEngine Coolant Temperature Gage on page 3-50.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
message ENGINE OVERHEATED, STOP ENGINE is
displayed, an overheat protection mode which alternates
®ring groups of cylinders helps prevent engine damage.
In this mode, you will notice a loss in power and
engine performance. This operating mode allows your
vehicle to be driven to a safe place in an emergency;
you may drive up to 50 miles (80 km). 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 ªEngine Oilº in the Index.
5-27

50,000 Miles (83 000 km)
qChange automatic transaxle ¯uid and ®lter if the
vehicle is mainly driven under one or more of
these conditions:
þ In heavy city traffic where the outside
temperature regularly reaches 90ÉF (32ÉC) or
higher.
þ In hilly or mountainous terrain.
þ When doing frequent trailer towing.
þ Uses such as limousine service.
þ Uses such as high performance operation.
If you do not use your vehicle under any of these
conditions, the ¯uid and ®lter do not require change until
the message CHANGE TRANS FLUID appears on
the Driver Information Center.
52,500 Miles (87 500 km)
qRotate tires. SeeTire Inspection and Rotation on
page 5-64for proper rotation pattern and additional
information.(See footnote +.)
60,000 Miles (100 000 km)
qReplace passenger compartment air ®lter. If you
drive regularly under dusty conditions, the ®lter
may require replacement more often.qInspect throttle body bore and valve plates for
deposits, open the throttle valve and inspect all
surfaces. Clean as required.
An Emission Control
Service. (See footnote ².)
qRotate tires. SeeTire Inspection and Rotation on
page 5-64for proper rotation pattern and additional
information.(See footnote +.)
qReplace engine air cleaner ®lter. SeeEngine Air
Cleaner/Filter on page 5-19for more information.An Emission Control Service.
67,500 Miles (112 500 km)
qRotate tires. SeeTire Inspection and Rotation on
page 5-64for proper rotation pattern and additional
information.(See footnote +.)
75,000 Miles (125 000 km)
qInspect engine air cleaner ®lter. If necessary, replace
the ®lter. If vehicle is driven in dusty/dirty conditions,
inspect ®lter at every engine oil change. See
Engine
Air Cleaner/Filter on page 5-19for more information.An Emission Control Service. (See footnote ².)
qReplace passenger compartment air ®lter. If you drive
regularly under dusty conditions, the ®lter may require
replacement more often.
qRotate tires. See
Tire Inspection and Rotation on
page 5-64for proper rotation pattern and additional
information.(See footnote +.)
6-7

82,500 Miles (137 500 km)
qRotate tires. SeeTire Inspection and Rotation on
page 5-64for proper rotation pattern and additional
information.(See footnote +.)
90,000 Miles (150 000 km)
qReplace passenger compartment air ®lter. If you
drive regularly under dusty conditions, the ®lter
may require replacement more often.
qInspect throttle body bore and valve plates for
deposits, open the throttle valve and inspect all
surfaces. Clean as required.
An Emission Control
Service. (See footnote ².)
qReplace engine air cleaner ®lter. SeeEngine Air
Cleaner/Filter on page 5-19for more information.An Emission Control Service.
qRotate tires. SeeTire Inspection and Rotation on
page 5-64for proper rotation pattern and additional
information.(See footnote +.)
97,500 Miles (162 500 km)
qRotate tires. SeeTire Inspection and Rotation on
page 5-64for proper rotation pattern and additional
information.(See footnote +.)
100,000 Miles (166 000 km)
qReplace spark plugs.An Emission Control Service.
qChange automatic transaxle ¯uid and ®lter if the
vehicle is mainly driven under one or more of
these conditions:
þ In heavy city traffic where the outside
temperature regularly reaches 90ÉF (32ÉC) or
higher.
þ In hilly or mountainous terrain.
þ When doing frequent trailer towing.
þ Uses such as limousine service.
þ Uses such as high performance operation.
If you do not use your vehicle under any of these
conditions, the ¯uid and ®lter do not require change until
the message CHANGE TRANS FLUID appears on
the Driver Information Center.
150,000 Miles (240 000 km)
qDrain, ¯ush and re®ll cooling system (or every
60 months since last service, whichever occurs ®rst).
See
Engine Coolant on page 5-24for what to use.
Inspect hoses. Clean radiator, condenser, pressure
cap and neck. Pressure test the cooling system
and pressure cap.
An Emission Control Service.
qInspect engine accessory drive belt.An Emission
Control Service.
6-8

GM Mobility Program for Persons
with Disabilities
This program, available to
quali®ed applicants, can
reimburse you up to $1,000
toward aftermarket driver or
passenger adaptive
equipment you may require
for your vehicle (hand
controls, wheelchair/
scooter lifts, etc.).
This program can also provide you with free resource
information, such as area driver assessment centers and
mobility equipment installers. The program is available
for a limited period of time from the date of vehicle
purchase/lease. See your dealer for more details or call
the GM Mobility Assistance Center at 1-800-323-9935.
Text telephone (TTY) users, call 1-800-833-9935.
GM of Canada also has a Mobility Program. Call
1-800-GM-DRIVE (463-7483) for details. All TTY
users call 1-800-263-3830.
Roadside Service
Cadillac's exceptional Roadside Service is more than an
auto club or towing service. It provides every Cadillac
owner with the advantage of contacting a Cadillac
advisor and, where available, a Cadillac trained dealer
technician who can provide on-site service.
Each technician travels with a specially equipped
service vehicle complete with the necessary Cadillac
parts and tools required to handle most roadside repairs.
Cadillac Roadside Service
žcan be reached by dialing
1-800-882-1112, 24 hours a day, 365 days a year. This
service is provided at no charge for any warranty-covered
situation and for a nominal charge if the Cadillac is no
longer under warranty. Roadside Service is available only
in the United States and Canada.
Cadillac Owner PrivilegesŸ
Roadside Service provides several Cadillac Owner
PrivilegesŸ at ªno charge,º throughout yourCadillac
Warranty Period ± 48 months/50,000 miles (80 000 km).
7-6