GMC SIERRA 1998 Owners Manual

Loading Your Vehicle
~EE ~NER'S MANUAL FOR ADDITIONAL INFORMATION. TI
The CertificatiodTire label is found on the rear edge of
the driver's door or in the Incomplete Vehicle Document
in the cab.
The label shows the size of your original tires and the
inflation pressures needed to obtain the gross weight
capacity
of your vehicle. This is called the Gross Vehicle
Weight Rating (GVWR). The GVWR includes the
weight
of the vehicle, all occupants, fuel and cargo.
The CertificatiodTire label also tells you the maximum
weights for the front and rear axles, called Gross Axle
Weight Rating (GAWR).
To find 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.
And,
if you do have a heavy load, you should spread
it out.
A CAUTION:
In the case of a sudden stop or collision, things
carried in the bed of your truck could shift
forward and come into the passenger area,
injuring
you and others. If you put things in the
bed of your truck, you should make sure they are
properly secured.
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NOTICE:
Some vehicles may be equipped with RPO VYU
(snow plow prep package). With this option, the
payload your vehicle can carry is reduced when
a
snow plow is installed. Your vehicle can be
damaged if either the front or rear axle ratings,
or the GVW are exceeded.
As a general guideline, with a 650 Ib. (295 kg)
snow plow, the weight of the occupants and cargo
must not exceed
300 lb. (135 kg). However, this
may depend on the vehicle's option content.
Therefore, to help avoid vehicle damage:
0 Make sure the weight on the front and
rear axles does not exceed their respective
axle ratings.
GVW rating.
Total vehicle weight must not exceed the
NOTICE: (Continued)
I NOTICE: (Continued) I
If more cargo or passengers need to be
carried, appropriate counter ballast must
be installed rear of the rear axle and
properly secured.
0 See your dealer for advice and information
about using
a snow plow on your vehicle.
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
GAWR.
If' you do, parts on your vehicle can break,
or it can change the
way your vehicle handles.
These could cause you to lose control.
Also,
overloading can shorten the life of your vehicle.
Using heavier suspension components to get added
durability might not change your weight ratings.
Ask
your dealer to help you load your vehicle the right way.
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c
NOTICE:
Your warranty does not cover parts or
components that fail because of overloading.
If you put things inside your vehicle -- like suitcases,
tools, packages, or anything else
-- they go as fast as the
vehicle goes.
If you have to stop or turn quickly, or if
there is a crash, they’ll keep going.
Things you put inside your vehicle can strike and
injure people in a sudden stop or turn, or in a crash.
0 Put things in the cargo area of your vehicle.
Try to spread the weight evenly.
Never stack heavier things, like suitcases,
inside the vehicle
so that some of them are
above the tops
of the seats.
Don’t leave an unsecured child restraint in
your vehicle.
CAUTION: (Continued)
When you carry something inside the
vehicle, secure it whenever you can.
Don’t leave a seat folded down unless you
need to.
There’s also important loading information for off-road
driving in this manual. See “Loading Your Vehicle for
Off-Road Driving” in the Index.
Truck-Camper Loading Information
This label is inside your glove box. It will tell you if
your vehicle can carry a slide-in camper, how much
of a
load your vehicle can carry, and how to correctly spread
out your load. Also, it will help you match the right
slide-in camper to your vehicle.
When you carry a slide-in camper, the total cargo load
of your vehicle is the weight of the camper, plus
everything else added to the camper after it left
the factory,
everything in the camper and
all the people inside.
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The Cargo Weight Rating (CWR) is the maximum
weight of the load your vehicle can carry. It doesn’t
include the weight
of the people inside. But, you can
figure about
150 lbs. (68 kg) for each seat.
The total cargo load must not be more than your
vehicle’s CWR.
Refer
to the Truck Camper Loading Information label
in glove
box for dimensions A and B as shown in the
following illustration.
Use the rear edge of the load
floor for measurement
purposes. The recommended location for the cargo center
of gravity is at point
C for the CWR. It is the point where
the mass
of a body is concentrated and, if suspended at
that point, would balance the front and rear. Here
is an example of proper truck and camper match:
A. Camper
Center of Gravity
B. Recommended Center of Gravity Location Zone
The camper’s center
of gravity should fall within the
center
of gravity zone for your vehicle’s cargo load.
You must weigh any accessories or other equipment that
you add to your vehicle. Then, subtract this extra weight
from
the CWR. This extra weight may shorten the
center of gravity zone of your vehicle. Your dealer can
help you with this.
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If your slide-in camper and its load weighs less than the
CWR, the center
of gravity zone for your vehicle may
be larger.
Your dealer can help you make a good vehicle-camper
match. He’ll also help
you determine your CWR.
After you’ve loaded your vehicle and camper, drive to a
weigh station and weigh the front and rear wheels
separately. This will tell you
the loads on your axles.
The loads on the front and rear axles shouldn’t be more
than either of
the GAWRs. The total of the axle loads
should
not be more than the GVWR.
Open your driver’s door and look at the
CertificatiodTire label to find
out your GAWR
and GVWR.
If you’ve gone over your weight ratings, move or take
out some things until all the weight falls below the
ratings.
Of course, you should always tie down any
loose items when you load your vehicle or camper. When you
install and load your slide-in camper, check
the manufacturer’s instructions.
If you want more information
on curb weights, cargo
weights, Cargo Weight Rating and the correct center of
gravity zone for your vehicle, your dealer can help
you.
Just ask for a copy of “Consumer Information,
Truck-Camper Loading.”
Trailer Recommendations
You must subtract your hitch loads from the CWR for
your vehicle. Weigh your vehicle with the trailer attached,
so that you won’t go over the GVWR or GAWR.
You’ll get the best performance if you spread out the
weight
of your load the right way, and if you choose the
correct hitch and trailer brakes.
For more information, see “Trailer Towing”
in the Index.
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Camper Wiring Harness
(If Equipped)
~~~
A five-wire harness is stored under your vehicle. The
harness is located inside the frame rail and is even with
the front of the pickup box. This harness has a
30 amp
battery feed wire and no connector, and should be wired
by
a qualified electrical technician. After choosing an
aftermarket mating connector pair, have
the technician
attach one connector to the five-wire camper harness and
the other connector
to the wiring harness for the camper.
The technician can use the following color code chart
when connecting the wiring harness to your camper.
0 Brown: Rear Lamps
0 Yellow: Left Stoplamp and Turn Signal
0 Dark Green: Right Stoplamp and Turn Signal
0 White (Heavy Gage): Ground
0 Light Green: Back-up Lamps
When the harness is
not being used, store it in its
original place. Wrap the harness together and tie
it
neatly so it won’t be damaged.
Pickup Conversion to Chassis Cab
General Motors is aware that some vehicle owners
may consider having the pickup box removed and
a
commercial or recreational body installed. Before you
do so, first contact the GM Zone Office for your area for
information on such conversions specific
to this vehicle.
(See the “Warranty and Owner Assistance” booklet
for
Zone Office.) Owners should be aware that, as
manufactured, there are differences between a chassis
cab and a pickup with the box removed which may
affect vehicle safety. The components necessary to adapt
a pickup
to permit its safe use with a specialized body
should be installed by a body builder in accordance with
the information available from the Zone Office.
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Towing a Trailer
If you don’t 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.
Pull
a trailer only if you have followed all the
steps in this section. Ask your dealer for advice
and information about towing a trailer with
your vehicle.
NOTICE:
Pulling a trailer improperly can damage your
vehicle and result in costly repairs not covered by
your warranty.
To pull a trailer correctly, follow
the advice in this part, and see your dealer for
important information about towing a trailer
with your vehicle.
Every vehicle is ready for some trailer towing. If yours
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 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.
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If You Do Decide To Pull A Trailer
If you do, here are some important points:
0
0
0
0
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 if your trailer will
weigh less than
the capacity stamped on your step
bumper. You should always use a sway control
if
your trailer will weigh more than the capacity
stamped
on your step bumper. You can ask a hitch
dealer about sway controls.
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.
0 If you have an automatic transmission, you can tow
in OVERDRIVE
(a). You may want to shift the
transmission to
THIRD (3) or, if necessary, a lower
gear selection if the transmission shifts too often
(e.g., under heavy loads and/or
hilly conditions). If
you have
a manual transmission and you are towing
a trailer, it’s better not to use
FIFTH (5) gear. Just
drive
in FOURTH (4) gear (or, as you need to, a
lower gear).
Three important considerations have
to do with weight:
0 the weight of the trailer,
0 the weight of the trailer tongue
0 and the weight on your vehicle’s tires.
Weigl- - 3e 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.
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Use one of the following charts to determine how much
your vehicle can weigh, based upon your vehicle model
and options.
Maximum trailer weight is calculated assuming the
driver and one passenger are 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.
Above the
2,000 lbs. (908 kg) trailer rating, the engine
oil cooler
is required on C/K- 1500 and C/K-2500
models with gas engines. Refer
to the Trailering Guide
for oil cooler recommendations.
Above the
5,000 lbs. (2 270 kg) trailer rating,
heavy-duty or gas shock absorbers are required
on
C- 1500 models, and heavy-duty shock absorbers
or the off-road chassis package are required on
K- 1500 models.
C-1500 (2WD)
Engine (Trans.)
4.3L (Auto.)
4.3L (Manual)
5.0L (Auto.)
5.0L (Manual)
5.x
Axle Ratio 3.08
3.42
3.08
3.42
3.73
3.08
3.42
3.73
3.08
3.42
3.08
3.42
3.73
Max. Trailer Wt.
4,000 lbs. (1 800 kg)
5,000 lbs. (2 270 kg)
2,000 lbs.
(908 kg)
2,500 lbs.
(1 135 kg)
3,000 lbs.
(1 362 kg)
4,500 lbs.
(2 043 kg)
5,500 Ibs. (2 497 kg)
6,500 Ibs. (2 951 kg)
2,000 lbs.
(908 kg)
3,000 Ibs. (1 362 kg)
5,000 lbs. (2 270 kg)
6,000 lbs. (2 724 kg)
7,000 lbs. (3 178 kg)
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1 K-1500 (4WD)
~ Engine (Trans.) Axle Ratio 4.3L
(Auto.) 3.73
1 4.3L
(Manual)
i 5.0L (Auto.)
5
.OL (Manual)
5.7L 6.5L Diesel 3.73
3.42
3.73
3.42 3.73
3.42
3.73
3.42
3.73
Max. Trailer Wt.
5,000 lbs. (2 270 kg)
2,500 lbs. (1 135 kg)
5,000 lbs. (2 270 kg)
6,000 lbs. (2 724 kg)
2,500 lbs. (1 135 kg)
3,500 lbs. (1 589 kg)
5,500 lbs. (2 497 kg)
6,500 lbs. (2 951 kg)
6,000 lbs. (2 724 kg)
7,000 lbs. (3 178 kg) 5 .OL (Manual)
5.7L
6.5L Diesel
7.4L
C-2500 (2WD) Engine (Trans.) Axle Ratio
5.0L (Auto.) 3.42
3.73
3.42
3.73
3.42
3.73
4.10
3.42 3.73
4.10 3.73
4.10
Max. Trailer Wt.
5,500 lbs. (2 497 kg)
6,500 lbs. (2 951 kg)
3,000 lbs. (1 362 kg)
4,000 lbs. (1 800 kg)
6,000 lbs.
(2 724 kg)
7,000 lbs.3' (3 178 kg)
8,000 lbs. (3 632 kg)
6,500 lbs. (2 951 kg)
7,500 1bs.T (3
405 kg)
8,500 lbs. (3 859 kg)
9,000 lbs. (4 086 kg)
11,OOO lbs.* (4 994 kg)
?Vehicles with
8600 GVWR subtract 500 lbs. (227 kg).
*Fifth wheel hitch rating; weight distributing hitch
rating is limited to 10,000 lbs. (4 540 kg).
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