1994 GMC SIERRA cooling

I NOTICE:
Engine damage from running your engine without coolant isn’t \
covered
by your warranty.
If there seems to be no leak, start the engine again. See if the fan speed
increases when idle speed
is doubled by pushing the accelerator pedal down.
If it doesn’t, your vehicle needs service. Turn off the engine.
How to Add Coolant to the Coolant Surge lank
If you haven’t found a problem yet, but the coolant level isn’t at the COLD
mark add a 50/50 mixture of clean water (preferably distilled) and a proper
antifreeze at the coolant surge tank, but be sure the cooling system,
including the coolant surge tank pressure cap, is cool before you do
it. (See
“Engine Coolant”
in the Index for more information about the proper
coolant mix.)
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..I . ... . ;. ..
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 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 UfluSual 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.
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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.
Engine Coolant
The following explains your cooling system and how to add coolant when it
is low. If you have a problem with engine overheating, see “Engine
Overheating”
in the Index.
The proper coolant for your vehicle
will:
Give freezing protection down to -20 OF (-29”C), or -34°F (-37°C) in
Canada and for vehicles with the cold climate option.
Give boiling protection up to 258 OF ( 125 O C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they should.
What to Use
Use a mixture of one-half clean wuter (preferably distilled) and one-half
antifreeze that meets
“GM Specification 6038-M,” which won’t damage
aluminum parts.
You can also use a recycled coolant conforming to “GM
Specification 6038-M” with a complete coolant flush and refill. If you use
this mixture, you don’t need to add anything else.
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I NOTICE:
If you use an improper coolant mix, your engine could overheat
and be badly damaged.
The repair cost wouldn’t be covered by
your warranty.
Too much water in the mix can freeze and crack
the engine, radiator, heater core and other parts.
Some conditions, such as air trapped in the cooling system, can affect the
coolant level
in the radiator. Check the coolant level when the engine is cold
and follow the steps under “Adding Coolant” for the proper way to add
coolant.
If you have to add coolant more than four times a year, have your dealer
check your cooling system.
If you use the proper coolant, you don’t have to add extra
inhibitors or additives which claim to improve the system. These
can be harmful.
Adding Coolant -Gas Engines
To Check Coolant
The coolant recovery
tank
is located on the
passenger side at the
rear corner
of the
engine compartment.
When your engine
is cold, the coolant level should be at COLD, or a little
higher. When
your engine is warm, the level should be up to HOT, or a little
higher.
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NOTICE:
Your surge tank pressure cap is a unique 15 psi (105 kPa)
pressure-type cap for use with surge tank cooling systems only.
It must be tightly installed to prevent coolant
loss and possible
engine damage from overheating. Be sure the arrows on the cap
line up with the top tube
of the coolant surge tank.
Thermostat
Engine coolant temperature is controlled by a thermostat in the engine
coolant system. The thermostat stops
the flow of coolant through the
radiator
until the coolant reaches a preset temperature.
When
you replace your thermostat, an AC" thermostat is recommended.
Power Steering Fluid
NOTICE:
Always turn the engine off before checking or adding power
steering fluid. The power steering pump cap is close to the fan
and other moving parts.
How To Check Power Steering Fluid
Unscrew the cap and
wipe the dipstick
with
a clean rag. Replace
the cap and completely
tighten it. Then
remove the cap again
and
look at the fluid
level on the dipstick.
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Wheel Nut Torque
For vehicle with dual wheels, wnen the vehicle, wheel or Tasteners are new,
have the torque set at
the first 100, 1,000 and 6,000 miles (1 60, 1600 and
9600 km). Use the torque specified
in the appropriate Specification Chart
later
in this section.
Single Belt Accessory Drive
If your new vehicle uses a serpentine belt, it is lighter and more durable than
systems with several belts.
The belt runs over or around the pulleys on the engine.
A tensioner may be
used
to keep the belt tight at all times. The tensioner also makes replacing
the belt easier.
If you need to replace the belt, be sure to get the correct
replacement belt. Your dealership or parts supplier can help you with this.
The Accessory Drive belt Routing label on your vehicle will show
you how
to route
the belt your vehicle uses.
Windshield Wiper Blade Inserts
To replace the
windshield wiper
blade insert, lift the
wiper arm and rotate
the blade until
it is
facing away from the
windshield.
Unlatch
the end of the insert from the holding clips. Remove the insert and
slide a new
one in place. Make sure the blade is secured in the clips.
Air Conditioning
Every now and then have your dealership check your air conditioning
system
to be sure it has not lost any cooling ability. If you think the system
is not working properly, have your dealership check it out as soon as
possible.
The air conditioning
will not work when the temperature is below 40°F
(4°C).
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NOTICE:
The wrong wheel can also cause problems with bearing life,
brake cooling, speedometer/odometer calibration, headlight aim,
bumper height, vehicle ground clearance, and tire or tire chain
clearance to the body and chassis.
Used Replacement Wheels
Tire Chains
NOTICE:
If your vehicle has dual wheels or LT26Y75R16 size tires, don’t
use tire chains; they can damage your vehicle.
If you don’t have
dual wheels or
if you have a tire size other than LT265/75R16,
use tire chains only where legal and only when you must. Use
only SAE Class “S” type chains that are the proper size for your
tires. Install them on the tires of the rear axle. Tighten them as
tightly
as possible with the ends securely fastened. Drive slowly
and follow the chain manufacturer’s instructions.
If you can
hear the chains contacting your vehicle, stop and retighten them.
If the contact continues, slow down until it stops. Driving too
fast with chains on will damage your vehicle.
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Engine ldenfificafion - Diesel Engines
Engine
Type VIN Code
Fuel System
Produced
By
Emissions
6.5L
V8
P
Diesel
U.S.
LD
Wheel Nut Torque
MODEL
C 1500
K 1500 & C-K 2500
C-K 2500 (w/C6P)
C-K 3500-Single Rear
Wheels
C3500-Dual Rear Wheels
C3500 HD-Front
C3500 HD-Rear
6.5L
V8
S
Turbo Diesel
us.
LD
DESCRIPTION
5 bolts (I41nm)
6 bolts (14mm)
8 bolts ( I4mm)
8 bolts (14mm)
8 bolts (14mm)
5 bolts (5/8 in.)
10 bolts (5/8 in.)
6.5L
V8
F
Turbo Diesel
U.S.
HD
TORQUE
120 ft. Ibs. (160 Nom)
120 ft. lbs. ( 160 Nom)
120 ft. lbs. (160 Nom)
120 ft. lbs.
(1 60 Nom)
140 ft. Ibs. (190 Nom)
175
ft. lbs. (240 Nom)
175
ft. Ibs. (240 Nom)
Cooling System Capacity
ENGINE
4.3L
VIN QTY Without A/C* QTY With AlC*
2 10.9 Quarts (10.3 Liters) 10.9 Quarts (10.3 Liters)
5 .OL H 17.5 Quarts (16.5 Liters) 18 Quarts (17 Liters)
5.7L
K 17.5 Quarts (16.5 Liters) 18 Quarts (17 Liters)
5.7L w/3500
K 26.5 Quarts (25 Liters) 27 Quarts (25.5 Liters)
HD
6.5L P 25 Quarts (23.5 Liters)
6.5L
S 25 Quarts (23.5 Liters)
6.5L
F 26.5 Quarts (25 Liters)
7.4L
N 23 Quarts (22 Liters)
7.4L
w/3500 N 26.5 Quarts (25 Liters)
HD
25 Quarts (23.5 Liters)
25 Quarts (23.5 Liters)
26.5 Quarts (25 Liters)
25 Quarts (23.5 Liters)
28.5 Quarts (27 Liters)
After refill, the level MUST be checked as outlined under “Engine Cooling
System”
in Section 5.
*All quantities are approximate.
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