1994 GMC SIERRA engine

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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When the engine
compartment is
hot, the level
should be at the
FULL mark.
When the engine
compartment
is
cool, the level
should be at the
FULL COLD
mark.
What to Add
Refer to the Maintenance Schedule to determine what kind of fluid to use.
See “Recommended Fluids and Lubricants”
in the Index.
NOTICE:
When adding power steering fluid or making a complete fluid
change, always use the proper fluid. Failure
to use the proper
fluid can cause leaks and damage hoses and seals.
Hydro-Boost Brake System (Hydraulic Pump)
The power steering pump is also used as the Hyrdo-boost pump. Refer to
“Power Steering System”
in this section when checking fluid level or
adding tluid.
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To Check Brake Fluid
You can check the
brake fluid without
taking off the cap. Just
look at the windows
on the brake fluid
reservoir. The fluid
levels should be above
“MIN.” If they aren’t,
have your brake system checked to see
if there is a leak.
After work
is done on the brake hydraulic system, make sure the levels are
above
“MIN” and below the top of each window.
What to Add
When you do need brake fluid, use only DOT-3 brake fluid - such as
Delco Supreme
ll@ (GM Part No.1052535). Use new brake fluid from a
sealed container only, and always clean the brake fluid reservo\
ir cap before
removing it.
NOTICE:
Don’t let someone put in the wrong kind of fluid. For
example, just
a few drops of mineral-based oil, such as engine
oil, in your brake system can damage brake system parts so
badly that they’ll have to be replaced.
Brake fluid can damage paint, so be careful not to spill brake
fluid
on your vehicle. If you do, wash it off immediately. See
“Appearance Care” in the Index.
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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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Fluid Leak Check
After the vehicle has been parked for a while, inspect the surface under the
vehicle for water, oil, fuel or other fluids. Water dripping from the air
conditioning
system after it has been used is normal. If you notice fuel leaks
or fumes, the causes should be found and corrected at once.
Lubrication
Accelerator Control System
Your maintenance schedule will tell you how often the accelerator linkage
pivot points must be lubricated. See “Recommended
Fluids and Lubricants”
in the Tndex for the proper lubricant to use.
Accelerator cables and cruise control cables should not be lubricated.
Any
cab1e.s that are worn or are hard to pull should be replaced.
Hood Latches and Hood Hinge
Your maintenance schedule will tell you how often to lubricate the hood
latch and hood hinge assembly. See “Recommended Fluids and Lubricants”
in the Index for the proper lubricant to use.
Propeller Shaft Slip Splines
See your maintenance schedule to find out how often the. slip splines must
be lubricated. See “Recommended Fluids and Lubricants”
in the Index for
the proper lubricant to use.
Constant Velocity Joints
See your mamtenance schedule to find out how often the constant velocity
joints must be lubricated. See “Recommended Flui-ds and Lubricants”
in the
Index for the proper lubricant to use.
Body
Normal use of your vehicle will cause metal to metal wear at some points on
the cab and body if they are not lubricated.
For exposed surfaces, such as door checks, door lock bolts, lock striker
plates, dovetail bumper wedges, etc., a
thin film of engine oil should be
applied.
The seat adjusters and seat track should be lubricated
with chassis grease.
Door weather strips and rubber hood bumpers should be wiped clean with
a
rubber lubricant.
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Contact your dealer to learn how to prepare your vehicle for longer storage
periods.
Bulb Replacement
Before you replace any bulbs, be sure that all the lights are\
off and the
engine isn’t running.
Sealed Beam Headlights
I
1. Remove the four
screws from the
headlight retainer.
2. Pull the headlight
out and remove
the retainer.
3.
4.
5.
Unplug and
remove the
headlight.
Plug in the new
headlight and put
it in place.
Install the
retainer
to the
headlight and
tighten the
screws.
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Exhaust System
To help prevent damage to your exhaust system, do not continue to drive
your vehicle
if you notice:
Engine misfiring
Loss of performance
0 Other unusual operating conditions
Have your engine and exhaust system serviced regularly.
Three- Way Catalytic Converter (gas engines)
Your vehicle’s three-way catalytic converter is designed to reduce the
pollutants
in your vehicle’s exhaust. Use only unleaded fuel in your vehicle.
If you use leaded fuel, you could damage your three-way catalytic converter
and other engine components.
Three- Way Catalytic Converter (diesel engines)
Your vehicle’s thre.e-way catalytic converter is designed to reduce the
particulates
in your vehicle’s exhaust. If your vehicles three-way catalytic
converter ever needs to be replaced,
it must be replaced with a three-way
catalytic converter intended for use with diesel engines
only.
Engine Control Module System
(All TBI equipped vehicles and diesel engine
vehicles below
8,500 Ibs. GVWR)
Gasoline Engines
This system has an oxygen sensor (02 ) that helps keep your engine’s
air-fuel mixture at
a proper level. Use only unleaded fuel in your vehicle. If
you use leaded fuel, you could damage your oxygen sensor (02) and
three-way catalytic converter.
Diesel Vehicles Below 8,500 LBS. GVWR
This system monitors engine speed and throttle position. It adjusts exhaust
gas recirculation to limit emissions.
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Malfunction Indicator
(SERVICE ENGINE SOON) Lamp
The Malfunction Indicator (SERVICE ENGINE SOON) Lamp on your
instrument panel lets you know when
your emission system needs service.
The light
will come on briefly when you start your engine to let you know
that the system is working. If
it does not come on when you start your
engine,
or if it comes on and stays on while you’re driving, your system
may need service. Your vehicle should still be driveable, but
you should
have your system serviced right away.
Secondary Air hjection Reaction (AIR) System
You may have this system. It has a control valve that will direct air to where
it is needed. If the AIR system needs service, your Malfunction Indicator
(SERVICE ENGINE SOON) Lamp on your instrument panel will come on.
Loading Your Vehicle
SEE OWNERS MANUAL FOR ADDITIONAL INFORMATION
BlKG
The Certification/Tire
label is found on the
rear edge of the
driver’s door or
in the
Incomplete Vehicle
Document
in the cab.
The label shows
the size of your original tires and the inflation pressures
needed to obtain the gross weight capacity of your vehicle. This is called the
GVWR (Gross Vehicle Weight Rating). The GVWR includes the weight of
the vehicle, all occupants, fuel and cargo.
The Certification/Tire label also tells
you the maximum weights for the
front and rear axles, called Gross Axle Weight Rating (GAWR). To find out
the actual loads on your front and rear axles, you need to go to a weigh
station and weigh your vehicle. Your dealer can help you
with this. Be sure
to spread out your load equally
on both sides of the centerline.
Never exceed the GVWR for your vehicle, or
the GAWR for either the front
or rear axle.
And,
if you do have a heavy load, you should spread it out.
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