1997 GMC SIERRA Owners 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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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). 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:
0 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:
The trailer parts can withstand 3,OOO psi (20 650 Wa)
of pressure.
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.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
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