1993 CHEVROLET SUBURBAN check engine

Service & Appearance Care
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 they 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 parts. Also use
GM Engine Coolant Supplement (sealer) with a complete coolant change.
If
you use these, you don’t need to add anything else.
Adding only plain water to your cooling system can be dangerous.
I
Plain water, or some other liquid like alcohol, can boil before the \
proper 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. Us\
e
a 50/50 mix of clean water and a proper antifreeze.
jIi ,yo.w use an improper coolant mix, your engine .coutd overheat andi
badly damaged. The repair cost wouldn’t be covered by your warranty.’ TP~
much water in ;the mix can freeze and crack the engine, radiator, .heater
wre-ad -.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 th\
e engine is cold
and follow the steps under “Adding Coolant” for the prope\
r way to
add
coolant.
.. .. ..
If you have to add coolant mdre than four times a year, have your dealer
check
your cooling system.
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k
NOTICE
f YOU use the proper coolant, you don’t have to add extra inhibitors or
idditives which claim to improve the system. These can be harmful
Adding Coolant
‘1 L
L
L
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 shoul\
d be up
to HOT, or a little higher.
To Add Coolant: If you need more coolant, add the proper mix at the
coolant recovery tank.
I CAUTION
4
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 have to
add coolant at the radiator. Never turn the radiator pressure
I cap-even a little-when the engine and radiator are hot. I
Add coolant mix at the recovery tank, but be careful not to spill it.
~ ~~
1 CAUTION I
You can be burned if you spill coolant on hot engine parts. Coolant
- b contains ethylene glycol, and it will burn if the engine parts are hot
I enough. Don’t spill coolant on a hot engine. I
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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
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.
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Service & Appearance Care
Brake Master Cylinder
Your brake master cylinder is here. It is filled with DOT-3 brake fluid.
P
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.
.
4 If you---have too much brake fluid, it can spill on the engine. The fluid
will burnhhe engine is hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake fluid only when \
work
is done on the brake hydraulic system.
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
MIN
mark. If they aren’t, have your brake system checked to see if there is a leak.
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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.
NOTICE
DOT-5 silicone brake fluid can damage your vehicle. Don’t use it.
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
-]stem can damaae brake svstem parts
so badlv that 1 fll have to
be replaced.
Brake fluid can damage paint, so be careful nor IO spit1 Drake fluid on
your vehicle.
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 flui\
d 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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Service & Appearance Care
Hood Laiches 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 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, 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 ch\
assis 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 items.
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.
You should not use penetrating oils because they could wash out the factory
installed lubricant and cause the lock to bind. De-icers which contain alcohol
could also wash away the lubricant,
so be sure to lubricate the lock after
using a de-icer
of this type.
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Service & Appearance Care
Specification Charts
Replacement Parts
Replacement part numbers listed in this section are based on the latest
information available at the time
of printing, and are subject to change. If a
part listed in this manual is not the same as the part used in your vehicle
when
it was built, or if you have any questions, please contact your GM truck
dealer.
Engine identification
Liter VIN Fuel Produced
Displacement Type Engine Code System BY Emissions
5.7 V8 K TB I U.S., Can.
7.4 V8 N TB I us.
*
*
*Light Duty Emissions with 8500 GVWR and below or:
Heavy Duty Emissions with 8501 GVWR and
above.
TO291
Wheel Nut Torque
MODEL DESCRIPTION TORQUE
C 1500 5 bolts (14mm) 120 ft. Ibs. (1 60 Nmm)
K 1500, C-K 2500 6 bolts (1 4mm) 120 ft. Ibs. (160
N-m)
C-K 2500 8 bolts (14mm) 120 ft. Ibs. (160 Nem)
I TO2951
Cooling System Capacity
VIN QUANTITY*
ENGINE CODE Without NC With AIC
5.7L K 17.5 Quarts (16.5 Liters)
18 Quarts (1 7 Liters)
7.4- N 23 Quarts
(22 Liters) 25 Quarts (23.5 Liters)
*All quantities are approximate.
*After refill, the level
MUST be checked as outlined under “Engine Cooling
System” in Section
5.
TO292
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Crankcase Capacify
QUANTITY*
ENGINE VIN CODE Without Filter With Filter
5.7L K 4 Quarts (3.8 Liters) 5 Quarts (4.8 Liters)
7.4L N 6 Quarts (5.7 Liters) 7 Quarts (6.6 Liters)
*All quantities are approximate.
*After refill, the level MUST be checked as outlined under “\
Engine Oil
TO296
And Filter Recommendations” in Section
5.
Air Condifioning Refrigeranf Capacify
TYPE* QUANTITY
Refrigerant R-12 Front
AJC 3.0 Ibs. (1.360 kg)
Front and Rear AJC 4.25 Ibs. (1.927 kg)
*Not all air conditioning refrigerants are the same.
If the air conditioning
system in your vehicle needs refrigerant, be sure the proper r\
efrigerant is
used. If you’re not sure, ask your GM dealer. TO302
Fuel Tank Capacify
I -1
Utility Model-Standard 30 Gallons (113 Liters)
Wagon Model-Standard 42 Gallons (159 Liters)
All quantities are for a completely dry tank and are approxima\
te. TO2971
Service Replacemenf Part and Filfer Recommendations
5.7 (K)
6.2 (C)
6.2
(J)*
6.5 (F)*
-
Oil
Filter
PF5 1
PF35t PF35t
PF35
PF35
PF35
PF35
-
1
Air PCV
Cleaner Valve
A348C
cv774c
A348C cv774c
A644C
A644C
A91 7C
A348C cv774c
AI 7acw cv7agc
Spark**
Plugs
.CR43TS
.CR43TS
.CR43TS
-
.CR43TS i
use a PF51 oil filter
*Heavy Duty Emission Engine
**Use
AC copper-cored resistor type spark plugs.
Fuel
Filter
GF481
GF481
GF481
TP
1 006
TP 1 006
TP 1 006 G F48 1
Radiator
RC36
RC36
RC36
RC32
RC32
RC32
RC36
Cap
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