1993 GMC SIERRA service

Service & Appearance ,Care
Engine Coolant
r
PO593
The following explains your cooling system and how to add cool\
ant 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 -34°F (-37°C).
Give boiling protection up to 258°F (125°C).
Protect against rust and corrosion:
Help keep the proper engine temperature.
Let the warning lights and gages work as thiy should.
What to Use:
Use a ,mixture of clean water (preferably distilled), and antifreeze that meets
“GM Specification 6038-M,” which won’t damage aluminum p\
arts.
Also use
GM Engine Coolant Supplement (sealer) with a complete coolant change. If
you use these, you don’t need to add anything else.
,
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1 CAUTION
4 Adding only plain water to your cooling system can be dangerous.
Plain water, or some other liquid like alcohol, can boil before th(
)per coolant mix will. Your vehicle’s coolant warning system is set
for the proper coolant mix. With plain water or the wrong mix\
, your
engine could get too hot but you wouldn’t get the overheat warning.
Your engine could catch fire and you or others could be burned. Use
a
50/50 mix of clean water and a proper antifreeze.
NOTICE
If you use an improper coolant mix, your engine could overheat an\
d 1:
badly damaged. The repair cost wouldn’t be covered by your warranty. 1
much water in the mix can freeze and xk +?e t line 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 prope\
r way to add
coolant.
If you have the low coolant warning system, refer to the General Motors
Service Manual or see your dealer for the proper coolant
fill procedure. (To
purchase a Service Manual, see “Service Publications’’ in the Index.) Using
the wrong
fill procedure can cause a low coolant warning indication.
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.
-
NOTICE .I
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Service & Amearance Care
Adding Coolant
r
PO206
To Check Coolant: 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.
LOW
COOLANT
K2327
If this light comes on, it means you're low on engine coolant.
To Add Coolant: If you need more coolant, add the proper mix at the
coolant recovery tank.
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Service & Appearance Cam
Thermostat
Engine coolant temperature is controlled by a thermostat in the engine coolant
system. The thermostat stops the flow of coolant through the r\
adiator until the
coolant reaches a preset temperature.
When you replace your thermostat, an
AC@ thermostat is recommended.
Power Steering Fluid
K2630
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.
K2693
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Service & Appearance Care
Windshield Washer Fluid
To Add:
Open the cap labeled WASHER FLUID ONLY. Add washer fluid until the
bottle
is full.
K2469
- When using a concentrated washer fluid, follow the manufacturer \
instructions for adding water.
I Don’t mix water with ready-to-use washer fluid. Water can us\
e the
solution to freeze and damage your washer fluid tank and other parts
of the washer system.
Also, water doesn’t clean as well as was
I fluid.
1 Fill your washer fluid tank only 3/4 full when it’s very cold. This
I
allows for expansion, which could damage the tank if it is CnrnDletely
full.
I
Don’t use radiator antifreeze for your windshield washer. It can
. damage your washer system and paint.
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Service & Appearance Care
MIN mark. If they aren’t, have your brake system checked to see if there is a
leak.
t
After work is done on the brake hydraulic system, make sure t\
he 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
11 @ (GM Part No. 1052535). Use new brake fluid from a sealed
container only.
Hydro-Boost Brake System (Hydraulic Pump)
The power steering pump is also used as the Hydro-boost pump. Refer to
“Power Steering System” in this section when checking fluid level or adding
fluid.
Replacing Brake System Parts
The braking system on .a modern vehicle is complex. Its many parts have to
be of ‘top quality and work well together
if the vehicle is to have really good
braking. Vehicles we design and test have top-quality
GM brake parts in
them, as your vehicle does when it is new. When you replace parts
of your
braking system-for example, when your brake linings wear down and you
have
to have new ones put in-be sure you get new genuine GM
replacement parts. If you don’t, your brakes may no longer work properly. For
example, if someone puts in brake linings that are wrong for your vehicle, the
balance between your front and rear brakes can change; for the\
worse. The
’ braking performance you’ve come to expect can change in many other ways
if someone puts in the wrong replacement brake parts.
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Other Maintenance Items
Front Suspension and Steering Linkage
Your maintenance schedule will tell you how often to lubricate the fittings. See
“Recommended Fluids and Lubricants’’ in the Index for the proper lubricant to
use.
Front Wheel Bearings
Your vehicle has front wheel bearings that must be cleaned and repa\
cked.
Your maintenance schedule will tell you how often this must be done.
Front Shock Absorbers
The front shock absorbers of your vehicle do many things. They help the
vehicle ride smoothly and also control the travel
of the suspension system.
When the shock absorbers are serviced, any replacement shock absorber\
s
must be the same as the original equipment shock absorbers in both
extended length and strength.
1 NOTICE
If you use shock absomers that are nor me same as the original shock
I absorbers, the shock absorbers or suspension system could be da\
maged.
Wheel Nut Torque
For vehicles with dual wheels, when the vehicle, wheel or fast\
eners are new,
have the torque set at the first
100, 1,000 and 6,000 miles (160, 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 is 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 sh\
ow you how to
route the belt your vehicle uses.
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Service & Appearance Care
Windshield Wiper Blade Inserts
I -
r
PO232
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 conditi\
oning 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 bel\
ow 40°F
(4°C).
Fluid Leak Check
After the vehicle has been parked for a while, inspect the su\
rface 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 Index for the proper lubricant to use.
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