2008 CHEVROLET SUBURBAN fuel

Before Leaving on a Long Trip
To prepare your vehicle for a long trip, consider having
it serviced by your dealer/retailer before departing.
Things to check on your own include:
Windshield Washer Fluid:Reservoir full? Windows
clean — inside and outside?
Wiper Blades:In good shape?
Fuel, Engine Oil, Other Fluids:All levels checked?
Lamps:Do they all work and are lenses clean?
Tires:Are treads good? Are tires inated to
recommended pressure?
Weather and Maps:Safe to travel? Have
up-to-date maps?
Highway Hypnosis
Always be alert and pay attention to your surroundings
while driving. If you become tired or sleepy, nd a
safe place to park your vehicle and rest.
Other driving tips include:
Keep the vehicle well ventilated.
Keep interior temperature cool.
Keep your eyes moving — scan the road ahead
and to the sides.
Check the rearview mirror and vehicle instruments
often.
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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. You will need a
well-charged battery to restart the vehicle, and possibly
for signaling later on with the headlamps. Let the
heater run for a while.
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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
Slowly and cautiously spin the wheels to free your
vehicle when stuck in sand, mud, ice, or snow. See
Rocking Your Vehicle to Get It Out on page 4-34.
If your vehicle has a traction system, it can often help to
free a stuck vehicle. Refer to your vehicle’s traction
system in the Index. If the stuck condition is too severe
for the traction system to free the vehicle, turn the
traction system off and use the rocking method.
{CAUTION:
If you let your vehicle’s tires spin at high
speed, they can explode, and you or others
could be injured. The vehicle can overheat,
causing an engine compartment re or other
damage. Spin the wheels as little as possible
and avoid going above 35 mph (55 km/h) as
shown on the speedometer.
For information about using tire chains on your vehicle,
seeTire Chains on page 5-88.
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Refer to your vehicle’s tire and loading information
label for specic information about your vehicle’s
capacity weight and seating positions. The
combined weight of the driver, passengers, and
cargo should never exceed your vehicle’s capacity
weight.
Certication/Tire Label
A vehicle specic Certication/Tire label is
found on the rear edge of the driver’s door.
The label shows the size of your vehicle’s original
tires and the ination pressures needed to
obtain the gross weight capacity of your vehicle.This is called Gross Vehicle Weight Rating
(GVWR). The GVWR includes the weight of the
vehicle, all occupants, fuel, and cargo.
The Certication/Tire label also tells you the
maximum weights for the front and rear axles,
called Gross Axle Weight Rating (GAWR). To nd
out the actual loads on your front and rear
axles, you need to go to a weigh station and
weigh your vehicle. Your dealer can help you with
this. Be sure to spread out your load equally on
both sides of the centerline.
Never exceed the GVWR for your vehicle, or the
GAWR for either the front or rear axle.
The Certication/Tire label also contains
information about your Front Axle Reserve
Capacity.
And, if you do have a heavy load, you should
spread it out.
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The plow your vehicle can carry depends on many
things, such as:
The options your vehicle came with, and the weight
of those options.
The weight and number of passengers you intend
to carry.
The weight of items you have added to your
vehicle.
The total weight of any additional cargo you intend
to carry.
Say, for example, you have a 700 lb (318 kg) snow
plow. The total weight of all occupants and cargo inside
the cab should not exceed 300 lb (135 kg). This
means that you may only be able to carry one
passenger. But, even this may be too much if you have
got other equipment already adding to the weight of
your vehicle.
Here are some guidelines for safely carrying a snow
plow on your vehicle:
Make sure the weight on the front and rear axles
does not exceed the axle rating for each.
For the front axle, if more cargo or passengers must
be carried, appropriate counter ballast must be
installed rear of the rear axle. Counter ballast must
be properly secured so it will not move during driving.
Follow the snow plow manufacturer’s
recommendations regarding rear ballast. Rear
ballast may be required to ensure a proper front and
rear weight distribution ratio, even though the actual
weight at the front axle may be less than the front
axle rating.
The snow plow manufacturer or installer can assist
you in determining the amount of rear ballast
required, to help make sure your snowplow/vehicle
combination does not exceed the GVW rating, the
front and rear axle ratings, and the front and rear
weight distribution ratio.
The total vehicle must not exceed the GVW rating.
Front axle reserve capacity is the difference between
your front Gross Axle Weight Rating (GAWR) and the
front axle weight of your vehicle with full fuel and
passengers. Basically, it is the amount of weight you can
add to your front axle before reaching your front GAWR.
The front axle reserve capacity for your vehicle can be
found in the lower right corner of the Certication/Tire
label, as shown.
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For example, adding a 700 lb (318 kg) snow plow
actually adds more than 700 lbs (318 kg) to the front
axle. Using the formula, if the snow plow is 4 ft (122 cm)
in front of the front axle and the wheel base is 10 ft
(305 cm), then:
W = 700 lb (318 kg)
A = 4 ft (122 cm)
W.B. = 10 ft (305 cm)
(W x (A + W.B.))/W.B. = (700 x (4 + 10))/10 = 980 lbs
(445 kg)
So, if your vehicle’s front axle reserve capacity is more
than 980 lbs (445 kg), you could add the snow plow
without exceeding the front GAWR.
You can add heavier equipment on the front of the vehicle
if you compensate for it by carrying fewer passengers,
less cargo, or by positioning cargo towards the rear. This
has the effect of reducing the load on the front. However,
the front GAWR, rear GAWR, and the Gross Vehicle
Weight Rating (GVWR) must never be exceeded.
{CAUTION:
On some vehicles that have certain front
mounted equipment, such as a snow plow, it
may be possible to load the front axle to the
front gross axle weight rating (GAWR) but not
have enough weight on the rear axle to have
proper braking performance. If your brakes can
not work properly, you could have a crash. To
help your brakes work properly when a snow
plow is installed, always follow the snow plow
manufacturer or installer’s recommendation for
rear ballast to ensure a proper front and rear
weight distribution ratio, even though the
actual front weight may be less than the front
GAWR, and the total vehicle weight is less
than the gross vehicle weight rating (GVWR).
Maintaining a proper front and rear weight
distribution ratio is necessary to provide
proper braking performance.
Total vehicle reserve capacity is the difference between
your GVWR and the weight of your vehicle with full
fuel and passengers. It is the amount of weight you can
add to your vehicle before reaching your GVWR.
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Trailering is different than just driving your vehicle by
itself. Trailering means changes in acceleration, braking,
handling, durability and fuel economy. Successful,
safe trailering takes correct equipment, and it has to be
used properly.
That’s 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.
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’ll be driving. A good source for
this information can be state or provincial police.
Consider using a sway control. See “Hitches” later
in this section.
Don’t tow a trailer at all during the rst 500 miles
(800 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, don’t drive over 50 mph (80 km/h)
and don’t make starts at full throttle. This helps your
engine and other parts of your vehicle wear in at
the heavier loads.
You can tow in DRIVE (D). If the transmission shifts
too often (e.g., under heavy loads and/or hilly
conditions) you may want to shift the transmission
to a lower gear selection or enable the Tow/Haul
mode, if equipped. See “Tow/Haul Mode” later
in this section.
Three important considerations have to do with weight:
The weight of the trailer
The weight of the trailer tongue
The weight on your vehicle’s tires
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Operating the vehicle in Tow/Haul when lightly loaded
or with no trailer at all will not cause damage. However,
there is no benet to the selection of Tow/Haul when
the vehicle is unloaded. Such a selection when unloaded
may result in unpleasant engine and transmission
driving characteristics and reduced fuel economy.
Tow/Haul is recommended only when pulling a heavy
trailer or a large or heavy load.
Your vehicle may be equipped with Autoride
®which
further improves your vehicle’s ride while towing.
SeeAutoride
®on page 4-49for more information.
Hitches
It’s 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.
Weight-Distributing Hitches and Weight
Carrying Hitches
When using a weight-distributing hitch, the hitch must
be adjusted so the distance (A) remains the same both
before and after coupling the trailer to the tow vehicle.(A) Body to Ground Distance (B) Front of Vehicle
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