1993 GMC SIERRA engine

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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CAUTION
Turning the radiator pressure cap when the engine and radiator are
hot can allow steam and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will almost never h\
ave to
add coolant at the radiator. Never turn the radiator pressure cap-even a little-when the engine and radiator are hot.
Add coolant mix at the recovery tank, but be careful not to \
spill it.
You can be burned
if you spill coolant on hot engine parts. Coolant
mtains ethylene glycol, and
it will burn if the engine parts are hot
enough. Don’t spill coolant on a hot engine. ’
Radiator Pressure Cap
K2515
1
Your radiator pressure cap is a 15 psi (105 kPa) pressure-type cap
must be tightly installed to prevent coolant
loss and possible engine
damage from overheating. Be sure the arrows on the cap line up w
overflow tube on the radiator filler neck.
-
When you replace your radiator pressure cap, an ACa cap is recommended.
-
I
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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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When the engine compartment is hot, the level should be at the FULL
When the engine compartment is cool, the level should be at the FULL
mark.
COLD mark.
F
\’ ‘k
+- .”.’e--: E
K2694
What to Add:
Refer to the Maintenance Schedule to determine what kind of fluid to use.
See “Recommended Fluids and Lubricants’’ in the Index.
r
When adding power steering fluid or making a complete fluid change, I
always use the proper fluid. Failure to use the proper fluid can cause
leaks and damage hoses and seals.
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Brake Master Cylinder
Your brake master cylinder is here. It is filled with DOT-3 brake fluid.
K2470
There are only two reasons why the brake fluid level in your \
master cylinder
might go down. The first is that the brake fluid goes down to an acceptable
level during normal brake lining wear. When new linings are put in, the fluid
level goes back up. The other reason is that fluid is leaking out of the brake
system.
If it is, you should have your brake system fixed, since a leak means
that sooner or later your brakes won’t work well, or won’\
t work at all.
So, it
isn’t a good idea to “top
off” your brake fluid. Adding brake fluid won’t correct
a leak.
If you add fluid when your linings are worn, then you’ll have too
much fluid when you get new brake linings. You should add (or remove), \
brake fluid, as necessary only when work is done on the brake\
hydraulic
system.
CAUTION I
If you have too much brake fluid, it can spill on the engine. The fluid
and your vehicle could be damaged. Add
. ake fhid nnlv en wn
is done on the brake hydraulic system.
- will burn if the engine is hot enough. You or others could he burned
Refer
to the Maintenance Schedule to determine when to check your brake
fluid. See “Periodic Maintenance” in the index.
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 the
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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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Accelerator cables and cruise control cables should not be lubr\
icated. Any
cables that are worn or are hard to pull should be replaced. \
Remove external deposits from injector pump face cam on 6.2L d\
iesel
engines, when the engine is cold.
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 Lubrican\
ts” 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 maintenance schedule to find out how often the consta\
nt velocity
joints must be lubricated. See “Recommended Fluids and .Lubri\
cants” in the
Index for the proper lubricant to use.
80dy
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, lo\
ck 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 lightly coated with a
rubber lubricant.
Never use too much of any lubricant and be sure to wipe up any extra
lubricant when you are finished.
Your maintenance schedule
will tell you how often to lubricate these Ilems.
See “Recommended Fluids and Lubricants” in the Index for \
the proper
lubricant to use.
Lock Cylinders
To be sure your locks operate properly, they must be lubricated. \
Your vehicle’s
maintenance schedule
will tell you how often to lubricate them. See
“Recommended Fluids and Lubricants” in the Index for the proper lubricant to
use.
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