1994 GMC SIERRA four wheel drive

Towing From the Front
If you have a two-wheel drive vehicle, don’t have your vehicle towed on
the rear wheels, unless you must. If the vehicle must be towed on the rear
wheels, don’t go more than
35 mph (56 km/h) or farther than 50 miles
(80 km) or your transmission will be damaged. If these limits must be
exceeded, then the rear wheels have to be supported
on a dolly.
If your vehicle has the four-wheel drive option and
the transfer case is
engaged, a dolly must be used under the rear wheels when towing from the
front
.
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How to Check Lubricant
If the level is below
the bottom
of the filler
plug hole, you’ll need
to add some lubricant.
Add enough lubricant
to raise the level
to the
bottom of the filler
plug hole.
What to Use
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
Four- Wheel Drive
Most lubricant checks in this section also apply to four-wheel-drive
vehicles. However, they have two additional systems that need lubrication.
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how often to check the
lubricant. See “Periodic Maintenance Inspections”
in the Index.
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Brake Wear
Your vehicle has front disc brakes and rear drum brakes. If you have a
C 3500 HD model, it has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched
warning sound when the brake pads are worn and new pads are needed. The
sound may come and go or be heard
all the time your vehicle is moving
(except when you are pushing on the brake pedal firmly).
The brake wear warning sound means that sooner or later your
brakes won’t work well. That could lead to an accident.
When
you hear the brake wear warning sound, have your vehicle
serviced.
NOTICE:
Continuing to drive with worn-out brake pads could result in
costly brake repair.
Some driving conditions or climates may cause a brake squeal when the
brakes are first applied or lightly applied. This does not mean something is
wrong with your brakes.
If
you have rear drum brakes, they don’t have wear indicators, but if you
ever hear a rear brake rubbing noise, have
the rear brake linings inspected.
Also, the rear brake drums should be removed and inspected each time the
tires are removed for rotation or changing. When you have
the front brakes
replaced, have the rear brakes inspected, too.
Brake linings should always be replaced
as complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return to normal height, or if
there is a rapid increase in pedal travel. This could be a sign of brake
trouble.
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Service Replacement Part and Filter
Recommendations
- Gas Engines
Engine
VIN
Oil Filter
Air Cleaner Filter
PCV Valve
Spark Plugs*
Fuel Filter Radiator Cap
4.3L
z
PF52
A178CW. CV789C
.CR43TS
GF48
1
RC36
5.OL
H
PF1218T A348C
cv774c
.CR43TS GF48
1
RC36
5.7L
K
PF1218t A348C
cv774c
.CR43TS GF48 1
RC36
“four Wheel Drive Vehicle -use a PF52 oil filter
*Use AC copper-cored resister type spark plugs
Service Replacement Part and Filter
Recommendations
- Diesel Engines
Engine
VIN
Oil Filter
Air Cleaner
Fuel Filter Surge Tank Cap 6.5L
P
PF1218
A9 17C
TP 1006
RC33
6.5L
S
PF1218 A917C
TP 1006
RC33
7.4L
N
PF1218 A348C
cv774c
.CR43TS GF48
1
RC36
6.5L
F*
PF1218 A917C
TP 1006
RC33
“Heavy Duty Emission Engine
Air Conditioning Refrigerants
Not all air conditioning refrigerants are the same. If the air conditioning
system in your vehicle needs refrigerant, be sure the proper refrigerant is
used.
If you’re not sure, ask your GM dealer. For additional information, see
your “Warranty and Owner Assistance Information” booklet.
Air Conditioning Refrigerant Capacity
TYPE
Refrigerant R 134A
QTY
2.25 lbs. (1.020 kg)
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Fuses and Circuit Breakers
NAME CIRCUITS PROTECTED
Gages
Turn-B/U EMC/Ign
Ign. A
Brake
AC/Htr
Ctsy
Park LP
P. Lps
Stop/Haz.
Wiper
Radio
Acc/Ign.
Acc/Batt.
Crank
4WD
DRL
Cruise Control, 4 WD Display
Illum. Rear Window Defogger
Timer, Aux. Batt. Relay Feed,
Safety Belt Buzzer Timer, Cluster
Ign. Feed
Back-up Lamps,
Turn Signals
T.C.C., Air Diverter,
E.S.C.,
E.G.R., E.C.M. Ign., R.W.A.L.
Brake Switch
Throttle Body Injectors
R.W.A.L., Cluster-Speedo
H.V.A.C.
4WD, Aux. Batt. Relay
Dome Lamp, Cargo Lamp, Ctsy,
and Glove Box Lps. (TR-R), Radio
(Memory-Clock) Horn Relay, Horn
Feed, Cigar Lighter, Park
Lamps C49 SW Illum., Headlamp “On”
Warning,
Radio Illum., H.V.A.C. Illum. Haz.
Flasher, Seat Belt Buzzer, Stop
Lmps., R.W.A.L. Memory
Windshield Wiper, Washer
Radio Feed
Pwr. Windows
Door Locks, Rear Window
Defogger
Crank, Discreet
Four Wheel Drive
Daytime Running Lights
FUSE CIRCUIT
BREAKER
20 Amp
15 Amp
10 Amp
10 Amp
15 Amp
25 Amp
20 Amp
20 Amp
5 Amp
15 Amp
25 Amp
10 Amp
30 Amp
30 Amp
5 Amp
25 Amp
15 Amp
*An inline fuse is used
for the underhood lamp
Do not use fuses of higher amperage than those recommended above.
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Heater or A/C Control Lamp
Four Wheel Drive Indicator
rour Wheel Drive Shift Lever
Instrument Panel Compartment Lamp
Ashtray Lamp
Sunshade Vanity Mirror
"Crew Cab Only
LAMP OR BULB
INSTRUMENT PANEL
Transmission Indicator (PRNDL)
Daytime Running Lights Indicatory
Charging System Indicator Lamp
Instrument Cluster Illumination
--Gage Cluster
Instrument Cluster Illumination
-Tachometer Cluster
Headlamp Beam Indicator
Directional Signal Indicator
Brake Warning Indicator
Safety Belt Warning
Check Gages Indicator
Malfunction Indicator ("Service
Engine Soon") Lamp
Upshift Indicator
Glow Plugs Lamp*:$:
Low Coolant
Water
in Fuel Lamp*'$
Service Throttle Soon Lamp*"
194
161
194
194
I94 74
TRADE NO.
161
74
74
I94
I94 74 74
74
74 74
74
74
74
74
74
74
6
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Tf you are skilled enough to do some work on your vehicle, you will
probably want to get the service information
GM publishes. For information
on how
to obtain various service publications for your vehicle, see “Service
Publications”
in the Index. You will find a list of publications and an order
form
in the back of the book.
Scheduled Maintenance Services
This part tells you the maintenance services that you should have done and
the times you should schedule them. Your
GM dealer knows your vehicle
best and wants you to be happy with
it. If you go to your dealer for your
service needs, you’ll know that GM-trained and supported service people
will perform the work using genuine
GM parts.
These schedules are for vehicles that:
0 carry passengers and cargo within the recommended limits. You will
find these limits on your vehicle’s Certification Label. See “Loading
Your Vehicle’’ in the Index.
are driven on regular road surfaces, and within legal driving limits, as
described in Section 4 “Your Driving and the Road.”
0 are driven off-road in the recommended manner. See “Off Road
Driving With Your Four-wheel Drive Vehicle”
in the Index.
0 use the recommended fuel. See “Fuel” in the Index.
Selecting the Proper Maintenance Services
To find the proper maintenance schedule for your vehicle, you must know
two things. What engine your vehicle has, and how you
use your vehicle.
Your engine type will tell
you which chart to use, and your driving
conditions will tell
you which schedule to use. ’The charts are found later in
this section.
Selecting the Proper Maintenance Chart
Your engine type (Gasoline or Diesel) and its emissions classification (Light
Duty or Heavy Duty Emissions) will
tell you which maintenance chart to
use. Find your Vehicle Identification Number (VIN), and look at the eighth
character
to see what your engine code is. Then use the following Engine
Emissions Classifications tables
to find your emissions classification.
Your VIN is on the plate on the top left corner of your instrument
panel, the Certification Label and on the Service Parts Identification
Label. See “Vehicle Identification Number’’
in the Tndex.
If your engine has more than one emissions classification, look at your
Certification Label to see what your Gross Vehicle Weight Rating
(GVWR)
is. See “Loading Your Vehicle” in the Index.
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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 fluid level and add as needed.
Check constant velocity joints and axle seals for leaking.
I-- ~ lsfer 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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