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/A CAUTION:
To help avoid injury to you or others:
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Never let passengers ride in a vehicle that is
being towed.
Never tow faster than safe
or posted speeds.
Never tow with damaged parts not
fully secured.
Never get under your vehicle after it has
been lifted by the tow truck.
Always use separate safety chains on each
side when towing a vehicle.
For pickups (except cab chassis models),
use T-hooks on front of vehicle, J-hooks
on rear.
For cab chassis models, use J-hooks on
front and rear of vehicle.
I A CAUTION:
A vehicle can fall from a car carrier if it isn’t
adequately secured. This can cause
a collision,
serious personal injury and vehicle damage. The
vehicle should be tightly secured with chains or
steel cables before it is transported.
Don’t use substitutes (ropes, leather straps,
canvas webbing, etc.) that can be cut by sharp
edges underneath the towed vehicle.
When your vehicle
is being towed, have the ignition
key in the OFF position. The steering wheel should be
clamped in a straight-ahead position,
with a clamping
device designed
for towing service. Do not use the
vehicle’s steering column lock for this. The transmission
and transfer case,
if you have one, should be in
NEUTRAL (N) and the parking brake released.
Don’t have your vehicle towed
on the drive wheels
unless
you must. If the vehicle must be towed on the
drive wheels, be sure to follow the speed and distance
restrictions later
in this section or your transmission will
be damaged.
If these limitations must be exceeded, then
the drive wheels have to be supported on
a dolly.
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Front Towing
Tow Limits -- 35 mph (56 kdh), 50 miles (SO km)
If these limits must be exceeded, then the rear wheels
have
to be supported on n dolly.
Rear Towing
NOTICE:
Towing pickup models from the rear while loaded
with heavy cargo may cause the frame side rails
to flex sufficiently to allow the pickup box to contact the cab and
could cause damage to the
cab and/or box.
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Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the
clutch
is engaged, the fan spins fdster to provide more air
to cool the engine.
In most every day driving conditions,
the fan
is spinning slower and the clutch is not fully
engaged. This improves fuel economy and reduces fan
noise. Under heavy vehicle loading, trailer towing andor
high outside temperatures, the
fm speed increases as the
clutch more fully engages.
So you may hear an increase
in fan noise. This is normal and should not be mistaken
as the transmission slipping or making extra shifts.
It is
merely the cooling system functioning properly. The fan
will slow down when additional cooling is not required
and the clutch partially disengages.
You may also hear this
fm noise when you start
the engine.
It will go away as the fan clutch
partially disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving,
especially
if you maintain your tires properly. If air goes
out
of a tire, it’s much more likely to leak out slowly.
But if you should ever have a “blowout,” here are a few
tips about what
to expect and what to do:
If a front tire fails, the flat tire will create a. drag that
pulls the vehicle toward that side. Fake your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain
lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like
a skid and
ITMY require the same correction you’d use in
a skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to
go. It may be
very bumpy and
noisy, but you can still steer. Gently
brake to a stop
-- well off the road if possible.
If a tire goes tlat, the next part shows how to use your
jacking equipment to change
a flat tire safely.
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Rocking your vehicle to get it out:
First. turn your steering wheel left and right. That will
clear the area around your front wheels. Then shift back
and forth between REVERSE
(R) and a forward gear (or
with a manual transmission, between FIRST (1) or
SECOND (2) and REVERSE(R)), spinning the wheels
as little as possible. Release the accelerator pedal while
you
shift. and press lightly on the accelerator pedal
when the transmission is
in gear. If that doesn't get you
out after a few tries. you nlay need to be towed out. Or,
you
can use your recovery hooks if your vehicle has
them.
If you do need.to be towed out, see "Towing Your
Vehicle" in the Index.
Using the Recovery Hooks
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Automatic Transmission Fluid
When to Check a1 C’ -ge
A good time to check your auromarlc transmission fluid
level
is when the engine oil is changed.
Change both the fluid and filter every
50,000 miles
(83 000 km) if the vehicle’s GVWR is over 8,600 or
if the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
regularly reaches
90°F (32°C) or higher.
0 In hilly or mountainous terrain.
0 When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
If your vehicle’s GVWR is not over 8,600 and you do
not use your vehicle under any of these conditions, the
fluid and filter
do not require changing.
See “Scheduled Maintenance Services’’
in the Index.
How to Check
Because this operation can be a little difficult, you
may choose to have this done at your GM dealership
Service Department. If
you do it yourself,
be sure to follow all the instructions
here, or
you could get a false reading on the dipstick.
NOTICE:
Too much or too little fluid can damage your
transmission.
Too much can mean that some of
i the fluid could come out and fall on hot engine
~ parts or exhaust system parts, starting a fire. Be
sure to get an accurate reading if you check your
transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level
if you have been driving:
When outside temperatures are above 90°F (32°C).
0 At high speed for quite a while.
In heavy traffic -- especially in hot weather.
While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which
is 180°F to 200°F (82°C
to 93°C).
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Rear Axle
When to Chc d Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change
it. See
“Scheduled Maintenance Services”
in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you’ll need to add some lubricant. Add enough lubricant
to raise the level to the bottom
of the filler plug hole.
C3 (3500 HD) Trucks Equipped with
Dana Rear
Axle
Additional rear axle scheduled maintenance is required
on 3500 HD models equipped with Dana rear axles
when they are driven under the following conditions:
Extreme loading (at or near GVWR) or trailer
towing, and:
0 Operation above 45 mph (70 km/h) for extended
periods
of time
Vehicles used
in any of these conditions require the
rear axle lubricant be changed every 30,000 miles
(SO 000 km). Fluid capacity is 4.12 quarts (3.9 L).
What to Use
Refer to the Maintenance Schedule to determine what
kind
of lubricant to use. See “Recommended Fluids and
Lubricants”
in the Index.
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Short TripKity Maintenance Schedule -- Gasoline Engines
The services shown in this schedule up to 100,000 miles
(1 66 000 km) should be performed after 100,000 miles
(166 000 km) at the same intervals.
Footnotes
T The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that
the failure to perform this maintenance item will
not
nullify the emission warranty or limit recall liability
prior
to the completion of the vehicle‘s useful life.
We, however, urge that all recommended
maintenance services be performed at the indicated
intervals and the maintenance be recorded.
# Lubricate the front suspension, kingpin bushings,
steering linkage, transmission shift linkage, transfer
case shift linkage, parking brake cable guides, rear
driveline center splines, front axle propshaft splines
and brake pedal springs. Ball joints and kingpin
bushings should not be lubricated unless their
temperature is 10°F
(- 12°C) or higher, or they
could be damaged.
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Drive axle service:
Locking Differential
-- Drain fluid and refill at first
engine
oil change. At subsequent oil changes, check
fluid level and add fluid as needed. If driving in
dusty areas or towing a trailer, drain fluid and refill
every 15,000 miles
(25 000 km).
Standard Differential -- Check fluid level and add
fluid
as needed at every oil change. If driving in
dusty areas or towing a trailer, drain fluid and refill
every
I5,OOO miles (25 000 km).
More frequent lubrication may be required for
heavy-duty or off-road
use.
3500 HD Models with applications requiring extreme
overload/trailer towing conditions and high-speed
(above
45 mph or 70 kmh) conditions for extended
periods
of time must have the drive axle fluid changed
evey
30,000 miles (50 000 km). See “Recommended
Fluids and Lubricants’’
in this section.
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I Short TripKity Maintenance Schedule -- Gasoline Engines I
48,000 Miles (80 000 km)
0 Change engine oil and filter (or every
3 months, whichever occurs first).
An Emission Control Service.
0 Lubricate chassis components; see footnote #
(or every 3 months, whichever occurs first).
0 Check readfront axle fluid level and add
fluid as needed. Check constant velocity
joints and axle seals for leaking. w
DATE SERVICED BY ACTUAL MILEAGE
50,000 Miles (83 000 k
0 Change automatic transmission fluid
and filter
if the vehicle’s GVWR is over
8600 lbs. or if the vehicle is mainly driven
under one or more of these conditions:
- In heavy city traffic where the outside
temperature regularly reaches
90°F
(32°C) or higher.
- In hilly or mountainous terrain.
- When doing frequent trailer towing.
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