engine GMC SIERRA 1997 Workshop Manual

a If you have an automatic transmission, you can tow
in 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).
Three important considerations have to do with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle’s tires.
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. 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.
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4.3L (Manual) 5.0L
(Auto.)
5.0L (Manual)
5.7L
6.5L Diesel
C-1500 (2WD)
Engine (Trans.) Axle Ratio
4.3L (Auto.) 3 .OS
3.42
3.73
3.08
3.42
3.73
3 .OS
3.42
3.08
3.42 3.08
3.42
3.73
3.08
3.42
Max. Trailer Wt.
4,000 lbs. (1 800 kg)
5,000 lbs. (2 270 kg)
5,500 lbs. (2 497 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 lbs. (2 497 kg)
2,000 lbs. (908 kg)
3,000 lbs.
(1 362 kg)
5,000 lbs. (2 270 kg)
6,000
lbs. (2 724 kg)
7,000 lbs. (3 178
kg)
6,000 lbs. (2 724 kg)
7,000 lbs. (3 178 kg)
K-1500 (4WD)
Engine (Trans.)
4.3L (Auto.)
4.3L (Manual)
5.0L (Auto.)
5.0L (Manual)
5.7L
6.5L Diesel
Axle Ratio
3.73
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 95 1 kg)
6,000 lbs. (2 724 kg)
7,000
lbs. (3 178 kg)
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C-2500 (2WD) K-2500 (4WD)
5 .OL (Manual)
5.7L
Engine (Trans.) Axle Ratio Max. Trailer Wt.
5.0L (Auto.) 3.42 5,500 lbs. (2 497 kg)
3.42 3,000 lbs.
(1 362 kg)
3.42 6,000 lbs. (2 724 kg)
4.10
8,000 lbs. (3 632 kg)
6.5L Diesel 3.42 6,500 lbs. (2 951 kg)
(Auto.) 3.73
7,500 lbs. (3 405 kg)
4.10 8,500 lbs. (3 859 kg)
7.4L (Auto.) 3.73 9,000 lbs.* (4 086 kg)
4.10
1 I ,OOO lbs.** (4 994 kg)
3.73 6,500
lbs.
(2 95 1 kg)
3.73
4,000 lbs. (1 800 kg)
3.73 7,000 lbs.
(3 178 kg)
*Fifth wheel hitch rating; weight distributing hitch
rating is limited to 9,000 lbs. (4 086 kg).
**Fifth wheel hitch rating; weight distributing hitch
rating is limited to 10,000 lbs. (4 540 kg). 6.5L Diesel
Engine (Trans.) Axle Ratio Max. Trailer Wt.
5.7L
3.73 6,000 lbs. (2 724 kg)
4.10 7,500 lbs. (3 405 kg)
3.42 6,000 lbs. (2 724 kg)
4.10 8,000 lbs. (3 632 kg)
7.4L (Auto.) 3.73
8,500 lbs.* (3 859 kg)
4.10 10,500 lbs.** (4 767 kg)
*Fifth wheel hitch rating; weight distributing hitch
rating is limited to
8,500 lbs. (3 859 kg).
**Fifth wheel hitch rating; weight distributing hitch
rating is limited to 10,000 lbs. (4 540 kg).
3.73
6,500 lbs.
(2 951 kg)
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C-3500 (2WD) K-3500 (4WD)
6.5L Diesel
7.4L
Engine (Trans.) Axle Ratio Max. Trailer Wt.
5.7L 4.10 7,500 lbs. (3 405 kg)
4.10
8,000 lbs. (3 632 kg)
4.56
9,000 lbs. (4 086 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).
Engine(Trans.) Axle Ratio Max. Trailer Wt.
5.7L 4.10 7,000 lbs. (3 178 kg)
6.5L Diesel 4.10 7,500 lbs. (3 405 kg)
7.4L 4.10 10,000 lbs. (4 540 kg)
4.56 12,000 lbs.* (5 448 kg)
*Fifth wheel hitch rating; weight distributing hitch
rating is limited to
10,000 lbs. (4 540 kg).
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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 lbs. (4 540 kg).
K-3500 Crew Cab (4WD)
6.5L Diesel
7.4L
Engine (Trans.) Axle Ratio Max. Trailer Wt.
5.7L 4.10 6,500 lbs. (2 951 kg)
4.56
8,000 lbs. (3 632 kg)
4.10 7,500 lbs.
(3 405 kg)
4.10 10,000 lbs.* (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).
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C-3500 HD Chassis Cab
Engine (Trans.) Axle Ratio
Max. Trailer
Wt.
6.5L Diesel 4.63 9,000 lbs. (4 086 kg)
5.13 10,000 lbs. (4 540 kg)
4.63 12,000 lbs.*
(5 448 kg)
5.13
12,000 lbs.* (5 448 kg)
7.4L
*Fifth wheel hitch rating; weight distributing hitch
rating is limited to
10,000 lbs. (4 540 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 L1H 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 more information about your vehicle‘s
maximum load capacity.
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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.
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 km/h) to reduce the
possibility of engine and transmission overheating. If you have an automatic transmission, you can tow
in
AUTOMATIC 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).
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.
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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. Apply your regular brakes, but don't shift into
PARK
(P) yet for an automatic transmission, or into
gear for a manual transmission.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb
the load.
4. 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.
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.
c
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).
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When You Are Ready to Leave After
Parkine
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.
Trailer Wiring Harness
A seven-wire harness is stored under the rear end of
your vehicle, between
the frame rails. An electrical
connector will need to be installed at the trailer end of
the harness, by a qualified electrical technician. For
additional trailer wiring and towing information please
consult your
GM dealer. Securely attach the harness to
the trailer, then tape or strap
it to your vehicle’s frame
rail. Be sure you leave it loose enough
so the wiring
won’t bind or break when turning with the trailer, but
not
so loose that it drags on the ground. Store the
harness in its original position. Wrap the harness
together and tie
it neatly so it won’t be damaged. If you
tow
a trailer, your Center High-Mounted Stoplamp
(CHMSL) may not be properly visible from behind.
You
should select a trailer with a CHMSL on it or, if one is
not available, have one installed. See your
GM dealer
about how to connect your vehicle’s wiring
to a
trailer CHMSL.
Check periodically to see that all hitch nuts and bolts
are tight.
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Using a Transfer Case Mounted Power
Take-Off (Automatic Transmission)
1. Set the parking brake.
2. Turn the ignition off.
3. Shift the transfer case into NEUTRAL (N).
4. Shift the transmission into NEUTRAL (N).
5. Engage the PTO.
If you are going to drive the vehicle, shift the
transfer case into the range you want. Turn the
ignition to START. Then apply the regular brakes
and release the parking brake.
6. Shift the transmission to THIRD (3) to start the PTO.
7. Release the regular brakes to drive the vehicle.
Disengaging a Power Take-OFF
1. Turn the ignition off.
2. Put the transmission in PARK (P).
3. Release the PTO
4. Restart the engine.
Step-Bumper Pad
If your vehicle has a rear step bumper, it may be equipped
with a rear step pad at the center of the bumper.
If you will be using the
bumper to tow a trailer, you
must remove the center
cutout circle to install
the trailer ball. You must
also remove both outer
cutouts to attach the trailer
safety chains.
To remove the pad, lift the
edge
of the pad from the
rear of the bumper and
the pad releases from the
bumper holes, lift the
pad
off.
swing it forward. When
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