2007 CADILLAC DTS PROFESSIONAL engine

Hill and Mountain Roads
Driving on steep hills or mountains is different
from driving in at or rolling terrain.If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that
can make your trips safer and more enjoyable.
Keep your vehicle in good shape. Check
all uid levels and also the brakes, tires,
cooling system, and transaxle. These parts
can work hard on mountain roads.
{CAUTION:
If you do not shift down, the brakes could
get so hot that they would not work well.
You would then have poor braking or
even none going down a hill. You could
crash. Shift down to let the engine assist
the brakes on a steep downhill slope.
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{CAUTION:
Coasting downhill in NEUTRAL (N) or with
the ignition off is dangerous. The brakes
will have to do all the work of slowing
down. They could get so hot that they
would not work well. You would then have
poor braking or even none going down a
hill. You could crash. Always have the
engine running and your vehicle in gear
when you go downhill.
Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift to a lower gear when
you go down a steep or long hill.
Stay in your own lane when driving on two-lane
roads in hills or mountains. Do not swing wide
or cut across the center of the road. Drive at
speeds that let you stay in your own lane.
As you go over the top of a hill, be alert. There
could be something in your lane, like a stalled
car or an accident.
You may see highway signs on mountains that
warn of special problems. Examples are long
grades, passing or no-passing zones, a falling
rocks area, or winding roads. Be alert to these
and take appropriate action.
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You can run the engine to keep warm, but be
careful.
{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO
(carbon monoxide) gas to get inside. CO
could overcome you and kill you. You
cannot see it or smell it, so you might not
know it is in your vehicle. Clear away
snow from around the base of your
vehicle, especially any that is blocking the
exhaust pipe. And check around again
from time to time to be sure snow does
not collect there.
Open a window just a little on the side of
the vehicle that is away from the wind.
This will help keep CO out.
Run your engine only as long as you must. This
saves fuel. When you run the engine, make it go a
little faster than just idle. That is, push the
accelerator slightly. This uses less fuel for the
heat that you get and it keeps the battery charged.
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You will need a well-charged battery to restart the
vehicle, and possibly for signaling later on with
your headlamps. Let the heater run for a while.
Then, shut the engine off and close the window
almost all the way to preserve the heat. Start
the engine again and repeat this only when you
feel really uncomfortable from the cold. But do it as
little as possible. Preserve the fuel as long as
you can. To help keep warm, you can get out of
the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.
If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
In order to free your vehicle when it is stuck, you
will need to spin the wheels, but you do not
want to spin your wheels too fast. The method
known as rocking can help you get out when you
are stuck, but you must use caution.
{CAUTION:
If you let your vehicle’s tires spin at high
speed, they can explode, and you or others
could be injured. And, the transaxle or
other parts of the vehicle can overheat.
That could cause an engine compartment
re or other damage. When you are stuck,
spin the wheels as little as possible. Do not
spin the wheels above 35 mph (55 km/h) as
shown on the speedometer.
Notice:Spinning the wheels can destroy parts
of your vehicle as well as the tires. If you
spin the wheels too fast while shifting
the transaxle back and forth, you can destroy
the transaxle. SeeRocking Your Vehicle to
Get It Out on page 333.
For information about using tire chains on your
vehicle, seeTire Chains on page 426.
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Towing a Trailer
The Cadillac Professional Vehicle cannot tow
a trailer.
{CAUTION:
If you do not use the correct equipment
and drive properly, you can lose control
when you pull a trailer. For example, if the
trailer is too heavy, the brakes may not
work well — or even at all. You and your
passengers could be seriously injured.
You may also damage your vehicle; the
resulting repairs would not be covered by
your warranty. Pull a trailer only if you
have followed all the steps in this section.
Ask your dealer/retailer for advice and
information about towing a trailer with
your vehicle.Your vehicle can tow a trailer if it is equipped with
the proper trailer towing equipment. To identify
the trailering capacity of your vehicle, you should
read the information in “Weight of the Trailer”
that appears later in this section. Trailering
is different than just driving your vehicle by itself.
Trailering means changes in handling, durability
and fuel economy. Successful, safe trailering takes
correct equipment, and it has to be used properly.
That is the reason for this part. In it are many
time-tested, important trailering tips and safety
rules. Many of these are important for your safety
and that of your passengers. So please read
this section carefully before you pull a trailer.
Load-pulling components such as the engine,
transmission, wheel assemblies and tires
are forced to work harder against the drag of the
added weight. The engine is required to operate
at relatively higher speeds and under greater
loads, generating extra heat. What is more, the
trailer adds considerably to wind resistance,
increasing the pulling requirements.
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If You Do Decide To Pull a Trailer
If you do, here are some important points:
There are many different laws, including speed
limit restrictions, having to do with trailering.
Make sure your rig will be legal, not only where
you live but also where you will be driving.
A good source for this information can be state
or provincial police.
Consider using a sway control. You can ask a
hitch dealer/retailer about sway controls.
Do not tow a trailer at all during the rst
1,000 miles (1 600 km) your new vehicle
is driven. Your engine, axle or other parts
could be damaged.
Then, during the rst 500 miles (800 km) that
you tow a trailer, do not drive over 50 mph
(80 km/h) and do not make starts at full
throttle. This helps your engine and other parts
of your vehicle wear in at the heavier loads.
Obey speed limit restrictions when towing a
trailer. Do not drive faster than the maximum
posted speed for trailers, or no more than
55 mph (90 km/h), to save wear on your
vehicle’s parts.Three important considerations have to do
with weight:
The weight of the trailer
The weight of the trailer tongue
The total weight on your vehicle’s tires
Weight of the Trailer
How heavy can a trailer safely be?
It should never weigh more than 1,000 lbs
(454 kg). These are total maximum weights
including the load. But even that can be too heavy.
It depends on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to
pull a trailer are all important. It can also depend
on any special equipment that you have on
your vehicle, and the amount of tongue weight the
vehicle can carry. See “Weight of the Trailer
Tongue” later in this section for more information.
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Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the upper
limit for cold tires. You will nd these numbers on
the Tire and Loading Information Label. See
Loading Your Vehicle on page 333. Then be sure
you do not go over the GVW limit for your vehicle,
including the weight of the trailer tongue.
Hitches
It is important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough
roads are a few reasons why you will need the
right hitch. Here are some rules to follow:
The rear bumper on your vehicle is not
intended for hitches. Do not attach rental
hitches or other bumper-type hitches to it. Use
only a frame-mounted hitch that does not
attach to the bumper.
Will you have to make any holes in the body
of your vehicle when you install a trailer
hitch? If you do, then be sure to seal the holes
later when you remove the hitch. If you do
not seal them, deadly carbon monoxide (CO)
from your exhaust can get into your vehicle.
SeeEngine Exhaust on page 130. Dirt
and water can, too.
Safety Chains
You should always attach chains between your
vehicle and your trailer. Cross the safety
chains under the tongue of the trailer so that the
tongue will not drop to the road if it becomes
separated from the hitch. Instructions about safety
chains may be provided by the hitch manufacturer
or by the trailer manufacturer. Follow the
manufacturer’s recommendation for attaching
safety chains and do not attach them to the
bumper. Always leave just enough slack so you
can turn with your rig. And, never allow safety
chains to drag on the ground.
Trailer Brakes
Because your vehicle has anti-lock brakes, do not
try to tap into your vehicle’s hydraulic brake
system. If you do, both brake systems will not
work well, or at all.
Be sure to read and follow the instructions for the
trailer brakes so you will be able to maintain
them properly.
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Making Turns
Notice:Making very sharp turns while
trailering could cause the trailer to come in
contact with the vehicle. Your vehicle could be
damaged. Avoid making very sharp turns
while trailering.
When you are turning with a trailer, make wider
turns than normal. Do this so your trailer will
not strike soft shoulders, curbs, road signs, trees
or other objects. Avoid jerky or sudden
maneuvers. Signal well in advance.
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 /retailer. 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
are 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 is important to check
occasionally to be sure the trailer bulbs are
still working.
Driving on Grades
Reduce speed and shift to a lower gearbefore
you start down a long or steep downgrade. If you
do not shift down, you might have to use your
brakes so much that they would get hot and
no longer work well.
On a long uphill grade, shift down and reduce
your speed to around 45 mph (70 km/h) to reduce
the possibility of the engine and the transmission
overheating.
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