1994 GMC SIERRA heater

Engine Oil Additives
Don’t add anything to your oil. Your GM dealer is ready to advise if you
think something should be added.
When to Change Engine Oil
See if any one of these is true for you:
Most trips are less than 4 miles (6 km).
It’s below freezing outside and most trips are less than 10 miles
(16 km).
The engine is at low speed most of the time (as in door-to-door
delivery, or
in stop-and-go traffic).
You tow a trailer often.
Most trips are through dusty places.
The vehicle is frequently operated off-road.
If any one
of these is true for your vehicle, then you need to change your oil
and-filter every 3,000 miles (5 000 km) or 3 months - whichever comes
first.
Light Duty Emissions:
If none of them is true, change the oil every 7,500 miles (12 500 km) or
12 months
- whichever comes first. Change the filter at the first oil change
and at every other oil change after that.
Heavy Duty Emissions:
If none of them is true, change the oil every 6,000 miles (10 000 km) or
12 months - whichever comes first. Change the filter at the first oil change
and at every other oil change after that if mileage determines when you
change
your oil. If time determines when you change your oil, change the
filter each time you change your oil.
Engine Coolant Heater (Engine Block Heater)
An engine coolant heater can be a big help if you have to park outside in
very cold weather, 0°F (- 18°C) or colder. If your vehicle has this option,
see “Engine Coolant Heater
” in the Index.
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I NOTICE:
If you use an improper coolant mix, your engine could overheat
and be badly damaged.
The repair cost wouldn’t be covered by
your warranty.
Too much water in the mix can freeze and crack
the engine, 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 proper way to add
coolant.
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.
Adding Coolant -Gas Engines
To Check Coolant
The coolant recovery
tank
is located on the
passenger side at the
rear corner
of the
engine compartment.
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.
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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
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194
I94 74
TRADE NO.
161
74
74
I94
I94 74 74
74
74 74
74
74
74
74
74
74
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Driving (continued) AtNight
............................................... 4-24. 4.38
BackingUp
.................................................. 4-42
Defensive
.................................................... 4-2
Downhill
.................................................... 4-19
Freeway
...................................................... 4-29
Highway Hypnosis
............................................ 4-30
Hydroplaning
................................................ 4-27
InBlizzard
................................................... 4-35
InCity
...................................................... 4-28
InRain
...................................................... 4-26
In Sand, Mud, Ice, Or Snow
........................... 2-15,4-22, 5-40
InWater
..................................................... 4-23
Nightvision
................................................. 4-25
Off-Roading
................................................. 4-13
OnGrades
................................................... 4-43
On Hill and Mountain Roads .................................... 4-31
On Off-Road Hills
............................................ 4-16
On Snow or Ice
..................................... 2-15,433, 4-55
Skidding
.................................................... 4-12
Stuck in Deep Snow
...................................... 4-40, 5-40
Throughwater
.......................................... 2-15, 4-23
Uphill
...................................................... 4-17
Winter
...................................................... 4-33
WithaTrailer
................................................ 4-41
DrunkenDriving ................................................. 4-2
E
Electronic Heating/Air Conditioning (See “Heating”) Engine Adding Coolant
..................................... 5.14.5.17. 6-41
Coolant (Block) Heater
................................ 2.19.3-4. 6.23
Cold Weather Starting (Diesel)
................................... 2-17
Coolant
...................................... 5.13.5.20.6-92. 6.98
Coolant Temperature Gage
...................................... 2-79
Diesel
.................................................. 2.16. 6-5
Crankcase .............................................. 2.96. 6.93
Exhaust
................................................ 2.33. 6.64
FanNoise
................................................... 5-25
Identification
................................................. 6-89
Oil (See “Oil”)
RunningWhileParked
......................................... 2-33
Aircleaner
.................................................. 6-29
Noise Control System
.......................................... 6-16
Overheating
.................................................. 5-11
starting ................................................ 2.12. 2.16
Equipment. Add-on
............................................. 6-68
Exhaustsystem
............................................ 2.33. 6-64
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