service CHEVROLET SUBURBAN 1994 Repair Manual

DlES€L ENGINES - MAINTENANCE SCHEDULE Ifi
Item
No.
1
-
8 CDRV System Inspection*
9 Fuel Filter Replacement*
12 EGR System Inspection*
17 Engine Accessory Drive (Serpentine) Belt Inspection*
19 Shields and Underhood Insulation
20 Air Intake System InspectionAD
0 0
InspectionAH 0 0
21 Thermostatically Controlled Engine Cooling Fan 0 0
CheckAH-Every 12 Months or
22 Exhaust Pressure Regulator Valve
Inspection*
23 Tire and Wheel Rotation**
0 0
24 Drive Axle Service** 0 0 0 0
25 Brake Systems Inspection**
* An Emission Control Service
** See “Explanation of Scheduled Maintenance Services” in this section,
A A Noise Emission Control Service
H Applicable only to vehicles sold in the United States.
t This maintenance scheduled applies to all diesel engines available.
TO4
1 Oflo91 0
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DIESEL ENGINES - MAINTENANCE SCHEDULE 1fl
(continued)
THE SERVICES SHOWN ON THIS CHART UP TO 60,000 MILES (1 00 000 km) ARE TO BE
DONE AFTER 60,000 MILES AT THE SAME INTERVALS.
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Explanation Of Scheduled Maintenance Services
Below are explanations of the services listed in the maintenance charts.
The proper fluids and lubricants to
use are listed in this section. Make sure
whoever services your vehicle uses these.
All parts should be replaced and
all necessary repairs done before you or anyone else drives the vehicle.
1. ENGINE OIL AND OIL FILTER CHANGE* -ALWAYS USE SH
ENERGY CONSERVIJTG TI (GASOLINE ENGINE) OR CF-4/SH
(DIESEL ENGINE) QUALITY OILS OF THE PROPER VISCOSITY.
To determine the preferred viscosity oil for your vehicle’s engine
(e.g.
SAE 5W-30 or low-30), see “Engine Oil” in the Index.
2. CHASSIS LUBRICATION - Lubricate the front suspension, king
pin bushings, steering linkage, transmission, and transfer case shift
linkage, parking brake cable guides, rear driveline center splines and
front axle propshaft splines, brake pedal springs, and clutch pedal
springs at the intervals specified.
Ball joints and king pin bushings should not be lubricated unless their
temperature is
10°F (-12”C), or higher. When the weather is cold, let
them warm up before lubrication or they could be damaged.
Also, be sure to check all the vehicle fluid levels at this time.
3. CLUTCH FORK BALL STUD LUBRICATION (5-SPEED
MANUAL TRANSMISSION
WITH DEEP LOW ) - Not
applicable to utility or wagon models.
4. COOLING SYSTEM SERVICE*? - Drain, flush and refill system
with new coolant. See “Engine Coolant’’
in the Index for the proper
coolant and mixture to use
in your vehicle.
Also inspect the hoses and replace them
if they are cracked, swollen, or
deteriorated. Tighten all
hose clamps (except constant tension clamps).
Remove debris and clean
the outside of the radiator and air
conditioning condenser. Wash the radiator
neck. To ensure proper
operation, pressure test the radiator and cap.
5. AIR CLEANER FILTER REPLACEMENT* - Replace at every
30,000 miles (50 000 km) or more often under dusty conditions. Ask
your dealer for the proper replacement intervals
for your driving
conditions.
6. FRONT WHEEL BEARING REPACK (2-WHEEL DRIVE
ONLY)
- Clean and repack the front wheel bearings at each brake
relining, or at the specified interval, whichever comes first.
4’ An Emission Control Service
*A fluid loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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7. TRANSMISSION SERVICE;-
Automatic Transmission
- Change the transmission fluid and filter
every 15,000 miles
(25 000 km) for vehicles under 8,600 GVWR or
every 12,000 miles
(20 000 km) for vehicles over 8,600 GVWR if the
vehicle
is mainly driven under one or more of these conditions:
In heavy city traffic.
0 Where the outside temperature regularly reaches 90°F (32°C) or
higher.
In hilly or mountainous terrain.
Frequent trailer pulling.
0 Uses such as taxi, police, delivery or other commercial service.
If the vehicle is not used mainly under any
of these conditions, change
the fluid and filter every
30,000 miles (50 000 km) for vehicles under
8,600 GVWR or every 24,000 miles (40 000 km) for vehicles over
8,600 GVWR see “Automatic Transmission Fluid” in the Index for
more information.
Manual Transmission - Transmission fluid does not require periodic
changing.
8. CDRV SYSTEM INSPECTION* - Check the Crankcase
Depression Regulator Valve System for
any worn, plugged or collapsed
hoses. Have the system checked as described in the Service Manual.
9. FUEL FILTER REPLACEMENT*$ - Replace the fuel filter at the
specified interval or sooner if clogged.
10. SPARK PLUG REPLACEMENT* - Replace spark plugs with the
type listed in Section
6. See “Specification Charts” in the Index.
1 1. SPARK PLUG WIRE INSPECTION - Clean wires and inspect for
burns, cracks or other damage. Check the wire boot fit at the distributor
and at the
spark plugs. Replace wires as needed.
‘% An Emission Control Service
$The California Air Resources Board has determined that the failure to
perform this maintenance item will
not nullify the emission warranty or
limit recall liability prior to the completion of the vehicle useful life.
General Motors, however, urges that all recommended maintenance
services be performed at the indicated intervals and the maintenance be
recorded.
?A fluid loss in
these systems may indicate a problem. Have them
inspected and repaired at once.
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12.
13.
14.
15.
16.
17.
18.
19.
20.
EGR SYSTEM INSPECTION* - Conduct EGR SYSTEM CHECK
as described in the Service Manual.
ELECTRONIC VACUUM REGULATOR VALVE (EVRV)
INSPECTION*
- Inspect filter for excessive contamination or
plugging. If required, clean element with a solution of biodegradable
soap and water, let dry and reinstall element.
ENGINE TIMING CHECK AND DISTRIBUTOR CHECK (SOME
MODELS)*$
- Adjust timing to underhood label specifications.
Inspect
the inside and outside of the distributor cap and rotor for cracks,
carbon tracking and corrosion. Clean
or replace as needed,
FUEL TANK, CAP AND LINES INSPECTION*$ - Inspect the
fuel tank, cap and lines for damage or leaks. Remove fuel cap, inspect
gasket for an even filler neck imprint, and any damage. Replace parts
as needed.
THERMOSTATICALLY CONTROLLED AIR CLEANER
INSPECTION*A
- (If so equipped.) Inspect all hoses and ducts for
proper hook-up.
Be sure the valve works properly.
SINGLE ENGINE ACCESSORY DRIVE (SERPENTINE) BELT
INSPECTION*
- Inspect belt. Look for cracks, fraying, wear, and
proper tension. Adjust or replace
as needed.
Check all
fuel and vapor lines and hoses for proper hookup, routing,
and condition. Check that the purge valve works properly,
if equipped.
Replace as needed.
SHIELDS AND UNDERHOOD INSULATION INSPECTIONAV
- Inspect shields and underhood insulation for damage or looseness.
Adjust or replace
as required.
AIR INTAKE SYSTEM INSPECTIONAV - Check the air intake
system installation to see that gaskets are sealed properly and all hose
connections, fasteners, and other components are tight. Also check to
be sure that
the air cleaner housing is properly seated, that the cover fits
tightly, and the wing nuts are tight. Tighten connections and fasteners
or replace damaged parts
as required.
'% An Emission Control Service
ANoise Emission Control Service
P'Applicable only to vehicles sold
in the United States
$The California Air Resources Board
has determined that the failure to
perform this maintenance item will not nullify
the emission warranty or
limit recall liability prior to the completion of the vehicle \
useful life.
General Motors, however, urges that
all recommended maintenance
services be performed at the indicated intervals and the maintenance be \
recorded.
EVAPORATIVE CONTROL SYSTEM (ECS) INSPECTION* -
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2 I. THERMOSTATICALLY CONTROLLED ENGINE COOLING FAN INSPECTIONAI/
- (If so equipped.) Inspect all hoses and
ducts for proper hook-up. Be sure the valve works properly.
22. EXHAUST PRESSURE REGULATOR VALVE INSPECTION” -
Check that the valve works properly, Correct any binding. Inspect
hoses for cracks, chafing or decay. Replace parts as needed.
23. TIRE AND WHEEL ROTATION AND INSPECTION - For proper
wear and maximum tire life, rotate tires at the first 6,000 miles
(10 000
kilometers) for Schedule
I (+) or 7,500 miles (12 500 kilometers) for
Schedule
I1 (0) and then every 15,000 miles (25 000 kilometers)
thereafter. Follow the instructions and patterns shown
in Section 6.
Check tires for uneven wear or damage. If irregular or premature wear is
apparent, check wheel alignment. Also, check or damaged wheels. See
“Tires”
in the Index for more information.
For dual wheels, whenever the vehicle, wheels, or fasteners are new,
have the wheel fastener torque
set at the first 100, 1,000 and 6,000 miles
( 160, 1600 and 10 000 km).
Block the tires opposite
those being removed to keep the vehicle from
rolling.
24.
DRIVE AXLE SERVICE? - Check readfront axle fluid level and
add
as needed. Check constant velocity joints and axle seals for
leaking.
0 Locking differential - Drain fluid at first oil change and refill.
Check fluid
level and add as needed at subsequent oil changes. In
dusty areas, or trailer towing applications drain fluid at every
15,000 miles (24 135 kilometers) and refill.
Standard differential - Check fluid level and add as needed at
every oil change. In dusty areas, or trailer towing applications,
drain fluid every
15,000 miles (24 135 kilometers) and refill.
0 More frequent lubrication may be required on heavy-duty or
off-road
use.
:i: An Emission Control Service
ANoise Emission Control Service
VApplicable
only to vehicles sold in the United States
+A fluid
loss in these systems may indicate a problem. Have them
inspected and repaired
at once.
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25. BRAKE SYSTEM INSPECTION? - When the engine oil is
changed, inspect the
lines and hoses for proper hookup, binding, leaks,
cracks, chafing, etc. Check
the parking brake adjust, and the fluid level
in the master cylinder.
A low fluid level can indicate worn disc brake
pads which may need to be serviced.
When the wheels are removed for rotation, inspect disc brake pads for
wear and rotors for surface condition. Also inspect drum brake linings
for wear and cracks. Inspect other brake parts, including drums, wheel
cylinders, parking brake, etc., at
the same time. Remove any rust or dirt
from the wheel and mounting surfaces before mounting
the wheel.
Inspect brakes more often if driving habits or conditions resul\
t in
frequent braking.
Owner Checks and Services
Listed below are owner checks and services which should be made at the
time period specified to help ensure proper safety, emission performance,
and dependability of your vehicle.
Be
sure any necessary repairs are completed at once. Whenever any fluids
or lubricants
are added to your vehicle, make sure they are the proper ones,
as shown in this Section.
At Least Once a Month
Tire inflation pressure check - Check the tires for proper inflation. If
they are low, inflate them to the level specified on the Certificatiomire
label or on the tire inflation charts. See “Loading Your Vehicle” or
“Inflation-Tire Pressure”
in the Index.
At Least Once a Year
Key lock cylinder lubrication - Lubricate key lock cylinders with engine
oil. See the “Recommended Fluid and Lubricants” chart
in this section.
Transmission neutral or clutch start switch operation -
?A fluid loss in these systems may indicate a problem. Have them inspected
and repaired at once.
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Lap and Shoulder Belts Condition and Operation - Inspect belt system,
including webbing, buckles, latch plates, retractors, guide loops\
and
anchors. Have
a belt assembly replaced if the webbing has been cut or
otherwise damaged.
Body Lubrication Service - Lubricate all body door hinges with engine
oil.
Also lubricate the tailgate, tailgate handle pivot points, and tailgate
mounted spare tire carrier (if equipped). Lubricate the body hood,
fuel door
and rear compartment hinges, latches and locks including interior glove box
and console doors, and any folding seat hardware. Lubricate the hood safety
lever pivot and prop rod pivot. More frequent lubrication may be required
when exposed to
a corrosive environment.
Periodic Maintenance Inspections - Listed below are inspections and
services which should be performed at least twice
a year (for instance each
spring or fall). You should let your
GM dealer’s service department or other
qualified service center do
these jobs. Make sure any necessary repairs are
completed at once.
Steering and Suspension Inspection? - Inspect front and rear suspension
and steering system for damaged, loose or missing parts, signs
of wear or
lack of lubrication. Inspect power steering lines and hoses for proper
hook-up, binding, leaks, cracks, chafing, etc. Lubricate the steering linkage.
Accelerator Control System - On gasoline engines, lubricate the pivot at
the
TBI throttle lever stud with engine oil. Do not oil any accelerator or
cruise control cables. Replace any cables that have high effort or excessive
wear.
Exhaust System Inspection - Inspect the complete system including the
three-way catalytic converter. Inspect the body near
the exhaust system.
Look for broken, damaged, missing or out-of-position parts,
as well as,
open seams, holes, loose connections or other conditions which could cause
a heat buildup
in the floor pan or could let exhaust fumes seep into the
passenger compartments.
Drive Axle Service? - Check readfront axle tluid level and add as needed,
Check constant velocity joints and axle seals for leaking.
Transfer Case (Four-wheel Drive) Inspection+ - Every 12 months or at
oil change intervals, check front axle and transfer case and add lubricant
when necessary. Oil the control lever pivot point and all exposed control
linkage. Check
vent hose at transfer case for kinks and proper installation.
More frequent lubrication may be required on heavy-duty or off-road use.
?A fluid loss in these systems may indicate a problem. Have them inspected
and repaired at once.
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Recommended FIuids & Lubricants
NOTE: Fluids and lubricants identified below by name, part number or
specification may
be obtained from your GM Dealer.
USAGE
Engine Oil - Gasoline
Engines
Engine Oil
- Diesel Engines
Engine Coolant Hydraulic Clutch System
Hydraulic Brake Systems Parking Brake Cables
Power Steering System Automatic Transmission
FLUIDLUBRICANT
API service SH or SG Energy
Conserving
I1 oils of the recommended
viscosity. The
“SH” designation may be
shown alone or
in combination with
others, such as “SH/CD,”
“SH, SG,
CD,”“SG/CD,” etc. To determine the
preferred viscosity for your vehicle’s
engine, see “Engine Oil”
in the Index.
API service CF4SH. The “CF4SH”
designation may be shown alone or
in
combination with others, such as
“CF-4/SG,” “CE/SH” or “CE/SG,” etc.
The designation may also be listed
in
reverse order, such as “SH/CF-4.” To
determine the preferred viscosity for
your vehicle’s engine, see “Engine Oil”
in the Index.
Mixture
of water and a good quality
ethylene glycol base antifreeze
conforming to “GM Specification
6038-M” (GM Part
No. 1052753), or
approved recycled coolant conforming to
“GM Specification 6038-M” with a
complete coolant flush and refill.
Hydraulic Clutch Fluid
(GM Part No.
12345347 or equivalent).
Delco Supreme
11 @ brake fluid (GM
Part
No. 1052535 or equivalent DOT-3
brake fluid).
Chassis Lubricant (GM Part
No.
12346003 or equivalent) or lubricant
meeting requirements of
NLGI Grade 2,
Category LB or GC-LB.
GM
Power Steering Fluid (GM Part
No. 10500 17 or equivalent) conforming
to “GM Specification
99850 10.”
DEXRON~ TTI or DEXRON~ IIE
Automatic Transmission Fluid.
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Maintenance Record
After each of the preceding Scheduled Maintenance Services is performed,
record the date, odometer reading, services performed (list
item numbers)
and who performed the services in
the appropriate column. In addition,
retain copies of your receipts. It
is suggested that receipts be kept with your
Owner's Manual.
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