1993 GMC SIERRA oil additives

Service & Appearance Care
Diesel Fuel Requirements
and Fuel System
Some states and provinces have restrictions on the purchase of diesel fuel
for light-duty vehicles and require you
to buy permits or pay special taxes.
Some of these restrictions apply only
to residents, and others apply to both
residents and visitors. These restrictions can change.
To learn the current
restrictions in any state or province, contact your auto club, \
the police or
other officials.
Fuel Requirements
1 NOTICE
Diesel fuel or fuel additives not recommended in this manual could
damage your fuel system and engine. Your warranty wouldn’t cover thi
damage. And:
Diesel fuel that has been mixed with engine oil could damage your
engine and emission controls.
Always check with your service station
his
diesel fuel, it can be difficult to restart your
engine. “Running Out of Fuel,” later
in this section, tells you how to
get
it started again. To avoid all this, try never to let. your tank get
What Fuel to Use:
You can use either Number I-D or Number 2-D diesel fuel, but you’ll get
better fuel economy using
2-D.
Diesel fuel may foam when you fill your tank. This can cause the automatic
pump nozzle
to shut off, even though your tank isn’t full. If this happens, just
wait for the foaming to stop and then continue to fill your tank.
1 CAUTION
- Heat coming from the engine may cause the fuel to expand and force
the fuel out of your tank. If something ignites the fuel, a \
fire could start
and people could be burned.
To help avoid this, fill your fuel tank only
until the automatic nozzle shuts
off. Don’t try to “top if off .” I
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These numbers on an oil container show its viscosity, or thickness.
Do not use other viscosity oils such as
SAE IOW-40 or SAE 2OW-50.
Energy Conserving II
Oils with these words on the container will help you save fuel.
This doughnut-shaped logo (symbol) is used on most oil containers to help
you select the correct oil.
You should look for this on the oil container, and use
only those oils that
display the logo.
GM Goodwrench@ oil (in Canada, GM Engine Oil) meets all the requirements
for your vehicle.
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 (5000 km) or 3 months-whichever comes
first.
Vehicles with Light Duty Emissions (8500 GVWR or less).
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.
Vehicles with Heavy Duty Emissions (8501 GVWR or more).
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 ea\
ch time
you change your oil.
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Service & Appearance Cam
heavy-duty applications at temperatures above freezing, 32°F (O’C), SAE
30 grade oil is recommended.
These numbers on an oil container show its viscosity, or thickness.
Do not use other viscosity oils such as
SAE IOW-40 or SAE 2OW-50.
This doughnut-shaped logo (symbol) is used on most oil contai\
ners to help
you select the correct oil.
You should
look for this on the oil container, and use only those oils that
display the logo.
GM Goodwrench@ oil (in Canada, GM Engine Oil) meets all the \
requirements
for your vehicle.
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
The engine is at low speed most of the time (as in door to door
You tow a trailer often.
Most trips are through dusty places. km).
delivery, or in stop-and-go traffic).
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 2,500 miles (4000 km) or 3 months-whichever comes
first.
If none of these is true, change the oil and filter every 5,000 miles (8000
km) or 12 months-whichever comes first.
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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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