NOTICE:
Driving with the parking brake on can cause your rear brakes to
overheat. You may have
to replace them, and you could also
damage other parts of your vehicle.
If you are towing a trailer and are parking on any hill: See “Towing a
Trailer” in the Index. That section shows what to do first to keep the trailer
from moving.
Propshaft Brake Burnish Procedure
If you have a 3500 HD model, it is recommended that the propshaft
mounted parking brake be burnished
as part of the new vehicle break in.
The parking brake will work best after it has been burnished following these
instructions.
Make
10 (ten) stops, using the parking brake foot pedal, from 20 mph
(32 kdh) about
2 1/2 miles (4 km) apart. In between stops, drive the
vehicle at
20 mph (32 km/h).
Torque Lock
The parking brake should be set first whenever you leave the driver’s seat.
If you are parked on
a hill and the transmission is placed in “P” (Park)
before
the parking brake is set, the weight of the vehicle may put too much
force
on the parking pawl in the transmission. It may be difficult to pull the
selector lever out
of “P’ (Park). This is called “torque lock.” To prevent this,
the parking brake should be set
BEFORE moving the gear selector to “P’
(Park).
When preparing to move
a vehicle parked on a hill, the selector lever should
be moved out of
“P’ (Park) BEFORE releasing the parking brake. Even
when
on level surfaces, its a good idea to set the parking brake first before
shifting
the transmission from “P” (Park).
If torque lock does occur, you may have to have another vehicle nudge your
vehicle uphill a little to take some
of the pressure off the transmission while
you pull the selector lever out of “P” (Park).
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5. Remove the key and take it with you. If you can walk away from your
vehicle with
the ignition key in your hand, your vehicle is in “P”
(Park).
Leaving Your Vehic/e With the Engine Running
(Automatic Transmission Models Only)
If you have to leave your vehicle with the engine running, be sure your
vehicle is
in “P” (Park) and your parking brake is firmly set before you
leave it. If you have four-wheel drive with a manual transfer case shift
lever, be sure that the transfer case
is in a drive gear - not in “N” (Neutral).
After you’ve moved the
shift lever into the “P’ (Park) position, hold the
regular brake pedal down. Then, see if
you can move the shift lever away
from “P” (Park) without first pulling it toward
you. If you can, it means that
the shift lever wasn’t
fully locked into “P” (Park).
Torque Lock (Automatic Transmission)
If you are parking on a hill and you don’t shift your transmission into “P”
(Park) properly,
the weight of the vehicle may put too much force on the
parking pawl
in the transmission. You may find it difficult to pull the shift
lever out of
“P’ (Park). This is called “torque lock.” To prevent torque lock,
set the parking brake and then shift into “P’ (Park) properly before you
leave
the driver’s seat. To find out how, see “Shifting Into ‘P’ (Park)” in the
Index.
When you are ready to drive, move the
shift lever out of “P” (Park)
BEFORE you release the parking brake.
If “torque
lock” does occur, you may need to have another vehicle push
yours
a little uphill to take some of the pressure from the transmission, so
you can pull the shift lever out of “P’ (Park).
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Defensive Driving
The best advice anyone can give about driving is: Drive defensively.
Please start with a very important safety device
in your Vehicle: Buckle up.
(See “Safety Belts” in the Index.)
Defensive driving really means “be ready for anything.” On city streets,
rural roads, or freeways,
it means “always expect the unexpected.’’
Assume that pedestrians or other drivers are going
to be careless and make
mistakes. Anticipate what they might do. Be ready for their mistakes.
Rear-end collisions are about the most preventable of accidents. Yet they
are common. Allow enough following distance. It’s the best defensive
driving maneuver, in both city and rural driving. You never know when the
vehicle in front of you is going to brake or turn suddenly.
Drunken Driving
Death and injury associated with drinking and driving is a national tragedy.
It’s the number one contributor to the highway death toll, claiming
thousands of victims every year. Alcohol takes away three things that
anyone needs
to drive a vehicle:
0 Judgment
Muscular Coordination
Vision
Police records show that almost half
of all motor vehicle-related deaths
involve alcohol
- a driver, a passenger or someone else, such as a
pedestrian, had been drinking. In most cases, these deaths are the result of
someone who was drinking and driving. About 20,000 motor
vehicle-related deaths occur each year because of alcohol, and thousands of
people are injured.
Just how
much alcohol is too much if a person plans to drive? Ideally, no
one should drink alcohol and then drive. But if one does, then what’s “too
much”? It can be a lot less than many might think. Although it depends on
each person and situation, here is some general information
on the problem.
The Blood Alcohol Content (BAC)
of someone who is drinking depends
upon four things:
0 How much alcohol is in the drink.
The drinker’s body weight.
0 The amount of food that is consumed before and during drinking.
0 The length of time it has taken the drinker to consume the alcohol.
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Driving Across an Incline
Sooner or later, an off-road trail will probably go across the incline of a hill.
If this happens, you have to decide whether to try to drive across the incline.
Here are some things
to consider:
0
0
0
A hill that can be driven straighr: up or aown may be too steep to drive
across. When you go straight
up or down a hill, the length of the wheel
base (the distance from the front wheels to the rear wheels) reduces the
likelihood the vehicle will tumble end over end. But when you drive
across an incline, the much more narrow track width (the distance
between the
left and right wheels) may not prevent the vehicle from
tilting and rolling over. Also, driving across an incline puts more
weight on the downhill wheels. This could cause
a downhill slide or a
rollover.
Surface conditions can be
a problem when you drive across a hill.
Loose gravel, muddy spots, or even wet grass can cause your tires to
slip sideways, downhill. If the vehicle slips sideways,
it can hit
something that will trip it (a rock, a rut, etc.) and roll over.
Hidden obstacles can make the steepness of the incline even worse. If
you drive across a rock with the uphill wheels, or if the downhill
wheels drop into a rut or depression, your vehicle can tilt even more.
For reasons
like these, you need to decide carefully whether to try to drive
across an incline. Just because the trail goes across the incline doesn’t mean
you have
to drive it. The last vehicle to try it might have rolled over.
Q: What if I’m driving across an incline that’s not too steep, but I hit
A: If you feel your vehicle starting to slide sideways, turn downhill. This
should help straighten out the vehicle and prevent the side slipping.
However, a much better way
to prevent this is to get out and “walk the
course”
so you know what the surface is like before you drive it.
some loose gravel and start to slide downhill. What should I do?
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Every vehicle is ready for some trailer towing. If it was built with trailering
options,
as many are, it’s ready for heavier trailers. But 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’s the reason for this section. 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.
If You Do Decide To Pull A Trailer
If you do, here are some important points.
There are many different laws having to do with trailering. Make sure
your rig will be legal,
not only where you live but also where you’ll be
driving. A good source for this information can be state or provincial
police.
Consider using a sway control if your trailer will weigh 4,000 pounds
(1 800 kg) or less. You should always use a sway control if your trailer
will weigh more than 4,000 pounds (I 800 kg).
You can
ask a hitch dealer about sway controls.
0 Don’t tow a trailer at all during the first 500 miles (800 km) your new
vehicle is driven. Your engine, axle or other parts could be damaged.
Then, during the first 500 miles (800 km) that you tow a trailer, don’t
drive over
50 mph (80 kdh) and don’t make starts at full throttle. This
helps your engine and other parts
of your vehicle wear in at the heavier
loads.
Three important considerations have
to do with weight:
Weight of the Trailer
How heavy can a trailer safely be?
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. And, it can also depend on any special equipment
that
you have on your vehicle.
You can ask your dealer for our trailering information or advice,
or you can
write us at
the address listed in your Warranty and Owner Assistance
Information Booklet.
In Canada, write to General Motors
of Canada Limited, Customer
Assistance Center,
1908 Colonel Sam Drive, Oshawa, Ontario LlH 8P7.
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Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight to measure
because
it affects the total or gross weight of your vehicle. The gross vehicle
weight (GVW) includes the curb weight of the vehicle, any cargo
you may
carry
in it, and the people who will be riding in the vehicle. And if you will
tow
a trailer, you must add the tongue load to the GVW because your
vehicle will be carrying that weight, too. See “Loading Your Vehicle”
in the
Index for more information about your vehicle’s maximum load capacity.
A B
If you’re using a “dead-weight” hitch, the trailer tongue (A) should weigh
10% of the total loaded trailer weight (B). If you have a
“weight-distributing” hitch, the trailer tongue (A) should weigh 12% of the
total loaded trailer weight
(B).
After you’ve loaded your trailer, weigh the trailer and then the tongue,
separately,
to see if the weights are proper. If they aren’t, you may be able to
get them right simply by moving some items around
in the trailer.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inflated to the limit for cold tires. You’ll find
these numbers
on the Certification label at the rear edge of the driver’s door
or
see “Tire Loading” in the Index. Then be sure you don’t go over the
GVW limit for your vehicle.
Hitches
It’s important to have the correct hitch equipment. Crosswinds, large trucks
going
by, and rough roads are a few reasons why you’ll need the right hitch.
Here are some rules
to follow:
0 If you use a step bumper hitch, and your trailer tongue has a V-shaped
foot, your bumper could be damaged in sharp turns. Check the distance
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from the front edge of the foot to the middle of the hitch ball socket. If
the distance is less than 12 inches, take the foot off the trailer tongue.
0 If you’ll be pulling a trailer that, when loaded, will weigh more than
4,000 pounds (1 8 14 kg) be sure to use a properly mounted,
weight-distributing hitch and sway control
of the proper size. This
equipment is very important for proper vehicle loading and good
handling
when you’re driving.
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. Always leave just enough slack
so you can turn with
your rig. And, never allow safety chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 pounds (450 kg) loaded, then it needs
its own brakes
- and they must be adequate. Be sure to read and follow the
instructions for
the trailer brakes so you’ll be able to install, adjust and
maintain them properly.
Your trailer brake system can tap
into your vehicle’s hydraulic brake system,
but consider
the following:
0 Will the trailer brake system use more than 0.02 cubic inch (0.3 cc) of
fluid from your vehicle’s master cylinder? If it will, don’t tap into your
vehicle’s brake system. Both braking systems won’t work well, and
you
could even lose your brakes altogether.
0 Will the trailer brake parts take 3,000 psi (20 650 kPa) of pressure? If
not, the trailer brake system must not be used with your vehicle.
If everything checks out this far, make the brake tap at the port on
the
master cylinder that sends the fluid to the rear brakes. But don’t use copper
tubing for this.
if you do, it will bend and finally break off. Use steel brake
tubing.
Driving with a Trailer
Towing a trailer requires a certain amount of experience. Before setting out
for the open road, you’ll want to get to know your rig. Acquaint yourself
with the feel of handling and braking with the added weight
of the trailer.
And always keep
in mind that the vehicle you are driving is now a good
deal longer and
not nearly so responsive as your vehicle is by itself.
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Things that burn can get on hot engine parts and start a fire.
These include liquids like gasoline or diesel fuel, oil, coolant,
brake fluid, windshield washer and other fluids, and plastic or
rubber. You or others could be burned. Be careful not to drop or
I spill things that will burn onto a hot engine.
Before closing the hood, be sure all filler caps are on properly. Pull down
the hood and close it firmly.
Cleaning Your Diesel Engine
NOTICE:
If you spray or pour water or any other liquid on your engine
when it is warm or hot, or when it is running,
you could cause
serious damage to it.
If you ever clean the engine, clean it only
when it is cold.
Noise Control System
The following information relates to compliance with Federal noise
emission standards for vehicles
with a Gross Vehicle Weight Rating
(GVWR) of more than
10,000 pounds (4 536 kilograms). The Maintenance
Schedule booklet provides information on maintaining the noise control
system to minimize degradation
of the noise emission control system during
the life of your vehicle. The noise control system warranty
is given in your
Warranty hooklet.
These standards apply only to vehicles sold
in the United States.
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