1998 GMC SIERRA Owners Manual

K-2500 (4WD)
Engine (Trans.) Axle Ratio Max. Trailer Wt.
5.7L 3.73 6,000 lbs. (2 724 kg)
3.73 6,500 Ibs.
(2 95 1 kg)
3.73
8,500 lbs. (3 859 kg)
4.10 10,500 lbs.* (4 767 kg)
4.10 7,500
lbs. (3 405 kg)
4.10 8,000 Ibs. (3 632 kg)
6.5L
Diesel
7.4L
*'Fifth wheel hitch rating; weight distributing hitch
rating is limited to 10,000 Ibs. (4 540 kg).
C-3500 (2WD)
6.5L Diesel
7.4L
Engine (Trans.) Axle Ratio Max. Trailer Wt.
5.7L 4.10 7,500 lbs. (3 405 kg)
4.56 9,000 lbs. (4 086 kg)
4.10
8,000 lbs. (3 632 kg)
4.10 10,500 lbs." (4 767 kg)
4.56 12,500 Ibs."
(5 675 kg)
"Fifth wheel hitch rating; weight distributing hitch
rating is limited
to 10,000 lbs. (4 540 kg).
K-3500 (4WD)
Engine (Trans.) Axle Ratio Max. Trailer Wt.
5.7L 4.10 7,000 lbs. (3 178 kg)
7.4L 4.10 10,000 lbs. (4 540 kg)
6.5L
Diesel 4.10 7,500 lbs. (3 405 kg)
4.56 12,000 lbs.* (5
448 kg)
*Fifth wheel hitch rating; weight distributing hitch
rating is limited to 10,000 Ibs. (4 540 kg).
C-3500 Crew Cab (2WD)
6.5L Diesel
7.4L
Engine (Trans.) Axle Ratio Max. Trailer Wt.
5.7L 4.10 7,000 lbs. (3 178 kg)
4.56 8,500 lbs.
(3 859 kg)
4.10 8,000 lbs.
(3 632 kg)
4.10 10,500
lbs." (4 767 kg)
4.56 12,500 lbs."
(5 675 kg)
*Fifth wheel hitch rating; weight distributing hitch
rating is limited to 10,000 Ibs. (4 540
kg).
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K-3500 Crew Cab (4WD)
Engine (Trans.)
5.7L
6.5L Diesel
7.4L
Axle
Ratio Max. Trailer Wt.
4.10 6,500 Ibs. (2 95 I kg)
4.56 8,000 lbs.
(3 ti32 kg)
4.10 7,500 Ibs.
(3 405 kg)
4.10
10,000 Ibs. (4 540 kg)
4.56 12,000
Ibs.'% (5 448 kg)
*Fifth wheel hitch rating; weight distributing hitch
rating is limited to
10,000 lbs. (4 540 kg).
C-3500 HD Chassis Cab
Engine (Trans.)
6.5L Diesel (Auto.)
7.4L
Axle
Ratio Max. Trailer Wt.
4.63 9,000 lbs. (4 084 kg)
5.1
3 10,OOO Ibs. (4 540 kg)
4.63
12,000 Ibs.'': (5 448 kg)
5.1
3 12,000 Ibs." (5 448 kg) 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 Communication Centre
1908 Colonel Sam Drive
Oshawa, Ontario
L1 H 8P7
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 mot-e information about
your vehicle's maximum load capacity.
"Fifth wheel hitch rating; weight distributing hitch
rating is limited
to 10,000 lbs. (4 540 kg).
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A B
If you’re using a weight-carrying hitch, the trailer
tongue (A) should weigh
10 percent of the total loaded
trailer weight
(B j. If you’re using a weight-distributing
hitch, the trailer tongue
(A) should weigh 12 percent 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 upper
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, including the
weight of the trailer tongue.
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:
If you use a step-bumper hitch, your bumper could
be damaged
in sharp turns. Make sure you have
ample room when turning to avoid contact between
the trailer and the bumper.
0 If you’ll be pulling a trailer that, when loaded, will
weigh more than
the capacity stamped on your step
bumper, 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.
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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
If your trailer weighs more than 1,000 Ibs. (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 the vehicle’s
hydraulic brake system only if
0 The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
0 The trailer’s brake system will use less than
0.02 cubic inch (0.3 cc) of fluid from your vehicle’s
master cylinder. Otherwise, both braking systems
won’t work well. You could even lose your brakes.
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 as
responsive as your vehicle
is by itself.
Before you start, check
the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires and mirror adjustment.
If the trailer has
electric brakes, start your vehicle and trailer moving and
then apply
the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
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During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as you
would when driving your vehicle without
a trailer. This
can help
you avoid situations that require heavy braking
and sudden turns.
Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re a good deal
longer,
you’ll need to go much farther beyond the
passed vehicle before you can return to
your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer
to the left, just move that hand
to the left.
To move the trailer to the right, move your
hand to the right. Always back up slowly and, if
possible, have someone guide you.
Making Turns
I 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’re turning with a trailer, make wider turns than
normal. Do this
so your trailer won’t 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
The arrows on your instrument panel will flash
whenever
you signal a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel
will flash 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.
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Driving On Grades
Reduce speed and shift to a lower gear before you 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 a long uphill grade, shift down and reduce your
speed
to around 45 mph (70 kdh) to reduce the
possibility
of engine and transmission overheating.
If you have an automatic transmission, you can tow in
AUTOMATIC OVERDRIVE
(@). 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).
When towing at high altitude
on steep uphill grades,
consider the following: Engine coolant
will boil at a
lower temperature than at normal altitudes. If you turn
your engine off immediately after towing
at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground) with
the automatic transmission in
PARK (P) (or the
manual transmission out of gear and the parking brake
applied) for a few minutes before turning the engine
off.
If you do get the overheat warning, see “Engine
Overheating’’ in
the Index.
Parking on Hills
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.
2.
3.
4.
Apply your regular brakes, but don’t shift into
PARK
(P) yet for an automatic transmission, or into
gear for a manual transmission.
Have someone place chocks under the trailer wheels.
When the wheel chocks are
in place, release the
regular brakes until the chocks absorb the load.
Reapply the regular brakes. Then apply your parking brake and
shift into PARK (P) for an automatic
transmission, or REVERSE (R)
for a manual
transmission.
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5. If you have a four-wheel-drive vehicle,
be sure the transfer case is in
a drive gear and not
in
NEUTRAL (N).
6. Release the regular brakes.
-
/r CAUTIOIA:
It can be dangerous to get out of your vehicle if
the shift lever is not fully in
PARK (P) with the
parking brake firmly set. Your vehicle can roll.
If you have left the engine running, the vehicle
can move suddenly. You or others could be
injured.
To be sure your vehicle won’t move, even
when you’re on fairly level ground, use the steps
that follow.
If you have four-wheel drive and your transfer
case is in
NEUTRAL (N), your vehicle will be free
to
roll, even if your shift lever is in PARK (P). So,
be sure the transfer case is in a drive gear -- not
in
NEUTRAL (N).
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
Release the parking brake.
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 transmission fluid (don’t
overfill), engine
oil, axle lubricant, belt, cooling system
and brake adjustment. Each of these is covered in this
manual, and the Index will help you find them quickly.
If you’re trailering, it’s a good idea to review these
sections before
you start your trip.
Check periodically
to see that all hitch nuts and bolts
are tight.
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Trailer Wiring Harness
A. Light-Duty Wiring Harness
B. Additional Heavy-Duty Wiring
C. Tie Straps
A eight-wire harness is stored under the rear end of your
vehicle. Five wires (A) are located between the rear
bumper and the spare tire, near the center. This wiring
harnewis tie-strapped to the taillamp and stoplamp
harness. Three wires (B) (light gauge white, blue and
orange) are located at
the rear left hand frame rail. 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 eight-wire trailer harness and the other connector
to the wiring harness on the trailer. Be sure that the
wiring harness on the trailer is strapped to the trailer’s
frame and leave
it loose enough so that the wiring
doesn’t bend or break, but not
so loose that it drags on
the ground. The technician can use the following color
code chart when connecting the wiring harness to
your trailer.
0 Brown: Rear Lamps
0 Yellow: Left Stoplamp and Turn Signal
0 Dark Green: Right Stoplamp and Turn Signal
0 White (Heavy Gauge): Ground
0 Light Green: Back-up Lamps
0 White (Light Gauge): Center High-Mounted
Stop Lamp
0 Blue: Auxiliary/Electric Trailer Brake Circuit
0 Orange: Fused Auxiliary Circuit
Store the harness
in its original place. Wrap the harness
together and tie
it neatly so it won’t be damaged.
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