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Stalling on an lncline
If your vehicle stalls when you’re crossing an incline, be sure you (and your
passengers) get out on the uphill side,
even if the door there is harder to
open.
If you get out on the downhill side and the vehicle starts to roll over,
you’ll be right in its path.
If you have to walk down the slope, stay out of the path the vehicle will take
if it does roll over.
1 A CAUTION:
Getting out on the downhill (low) side of a vehicle stopped across
an incline is dangerous.
If the vehicle rolls over, you could be
crushed or killed. Always get out on the uphill (high) side of the
vehicle and stay well clear
of the rollover path.
Driving In Mud, Sand, Snow, Or Ice
When you drive in mud, snow or sand, your wheels won’t get good traction.
You can’t accelerate
as quickly, turning is more difficult, and you’ll need
longer braking distances.
It’s best
to use a low gear when you’re in mud - the deeper the mud, the
lower
the gear. In really deep mud, the idea is to keep your vehicle moving
so you don’t get stuck.
When you drive on sand, you‘ll sense
a change in wheel traction. But it will
depend upon how loosely packed the sand
is. On loosely packed sand (as on
beaches or sand dunes) your tires will tend to sink into the sand. This has an
effect on steering, accelerating, and braking.
You may want to reduce the air
pressure in your tires slightly when driving
on sand. This will improve
traction.
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To wing Your Vehicle
Try to have your GM dealer or a professional towing service tow your
vehicle. They can provide the right equipment and know how to tow
it
without damage.
If your vehicle has been changed since
it was factory-new. by adding such
things like fog lamps, aero skirting,
or special tires and wheels, these things
could be damaged during towing.
Before you do anything,
turn on the hazard warning flashers.
When you call, tell the towing service:
0 That your vehicle has rear-wheel drive, or that it has the four-wheel
drive option.
The make, model, and year of your vehicle.
0 Whether you can move the shift lever for the transmission and transfer
case,
if you have one.
If there was an accident. what was damaged.
A CAUTION:
To help avoid injury to you or others:
Never let passengers ride in a vehicle that is being towed.
0 Never tow faster than safe or posted speeds.
0 Never tow with damaged parts not fuIly secured.
0 Never get under your vehicle after it has been lifted by the
tow truck.
0 Always use separate safety chains on each side when towing a
vehicle.
0 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.
When your vehicle is being towed, have the ignition key off. 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.
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Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the clutch is engaged,
the fan spins faster
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 and/or high outside temperatures, the fan
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 fan 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. Take your foot
off the accelerator pedal and grip the
steering wheel firmly, Steer
to maintain lane position, 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 may
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 flat, the next part shows how to use your jacking equipment to
change a flat tire safely.
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Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage by driving slowly to a
level place. Turn on your hazard warning flashers.
A. Flat Tire
B. Blocked Tire
The following steps will tell
you how to use the jack and change a tire.
The equipment you’ll need
is behind the passenger’s seat. Turn the wing nut
counterclockwise and remove the jack cover, if there is one.
Your spare tire
is stowed under the truck bed, at the
rear.
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Front rosluon Rear Position
With UP on the ratchet facing you, raise the vehicle by rotating the ratchet
and wheel wrench clockwise. Raise the vehicle
far enough off the ground so
there is enough room for the spare tire to fit.
Remove
all the wheel
nuts and take
off the
flat tire,
A CAUTION:
Rust or dirt on the wheel, or on the parts to which it is fastened,
can make the wheel nuts become loose after a time. The wheel
could come
off and cause an accident. When you change a wheel,
remove any rust or dirt from the places where the wheel attaches
to the vehicle. In an emergency, you can use a cloth or a paper
towel
to do this; but be sure to use a scraper or wire brush later,
if you need to, to get all the rust or dirt off.
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What to Use
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants”
in the Index.
C3 (3500 H.D.) Trucks Equipped with Dana Rear Axle
Additional rear axle scheduled maintenance is required on 3500 H.D.
models equipped with Dana rear axles when they are driven under the
following conditions:
0 Extreme loading (at or near GVWR) or trailer towing, and:
Operation above 45 mph for extended periods of time
Vehicles used
in any of these conditions require the rear axle lubricant (SAE
8OW-90 - GL-5) be changed every 3 months or 3,000 miles, whichever
comes first.
To reduce required maintenance, SAE 75W-140 synthetic gear lubricant
may be used. With the use of synthetic
SAE 75W-140 lubricant, the fluid
change intervals may be increased to 30,000 miles. Before using SAE
75W-140, it is important to drain and flush the axle with clean mineral
based (non-synthetic) axle lubricant. Fluid capacity is 4.12 qts. (3.9L).
Four- Wheel Drive
Most lubricant checks in this section also apply to four-wheel-drive
vehicles. However, they have two additional systems that need lubrication.
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how often to check the
lubricant. See “Periodic Maintenance Inspections”
in the Index.
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If your engine has more than one emissions classification, the classification
is determined by the Gross Vehicle Weight Rating (GVWR) of your vehicle
as shown on the Certification Label. See “Loading Your Vehicle”
in the
Index.
Once you’ve determined your engine type and,
if necessary, emissions
classification, you’ll need to decide which of the two schedules is right for
your vehicle. See Definitions for Maintenance Schedule
I and Maintenance
Schedule
I1 following.
Schedule I Definition - Gasoline Engines With Light Duty
Emissions
Follow Maintenance Schedule I if any one of these is true for your vehicle:
iII Most trips are less than 5 to 10 miles (8 to 16 km). This is particularly
important when outside temperatures are below freezing.
0 Most trips include extensive idling (such as frequent driving in
stop-and-go traffic).
You operate your vehicle in dusty areas or off-road frequently.
0 You frequently tow a trailer.
Schedule
I should also be followed if the vehicle is used for delivery
service, police, taxi, or other commercial application.
Schedule I Intervals - Gasoline Engines With Light Duty
Emissions
Every
3,000 Miles (5 000 km) or 3 Months, Whichever Occurs First
Engine Oil and Filter Change
Chassis Lubrication
Drive Axle Service
At 6,000 Miles (10 000 km) - Then Every 12,000 Miles (25 000 km)
Tire Rotation
Every 75,000 Miles (25 000 km)
Air Cleaner Filter Inspection, if driving in dusty conditions
Front Wheel Bearing Repack
(or at each brake relining) (2WD Only)
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Schedule I Intervals - Gasoline Engines with Heavy Duty
Emissions
Every
3,000 Miles (5 000 km)
Engine Oil and Filter Change (or every 3 months, whichever occurs first)
Chassis Lubrication (or every
3 months, whichever occurs first)
Drive Axle Service
At 6,000 Miles (10 000 km) - Then Every 12,000 Miles (25 000 km)
Tire Rotation
Every 12,000 Miles (20 000 km)
Air Cleaner Filter Inspection, if Driving in Dusty Conditions
Front Wheel Bearing Repack (or at Each Brake Relining) (2-Wheel Drive
Only
1
Fuel Filter Replacement
Engine Accessory Drive Belt Inspection
Shields
and Underhood Insulation Inspection
Thermostatically Controlled Engine Cooling Fan Check (or every
12
months, whichever occurs first)
Every 24,000 Miles (40 000 km)
Cooling System Service (or every 24 months, whichever occurs first)
Air Cleaner Filter Replacement
Engine Timing Check
Thermostatically Controlled Air Cleaner Inspection
Air Intake System Inspection
Every 27,000 Miles (45 000 km)
Spark Plugs Replacement
Every 30,000 Miles (50 000 km)
Clutch Fork Ball Stud Lubrication (%Speed Transmission with Deep-Low
Only)
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