gas mileage GMC ENVOY 2003 Owner's Manual

As in the chart shown previously, SAE 5W-30 is the
only viscosity grade recommended for your vehicle. You
should look for and use only oils which have the API
Starburst symbol and which are also identi®ed as
SAE 5W-30. If you cannot ®nd such SAE 5W-30 oils,
you can use an SAE 10W-30 oil which has the API
Starburst symbol, if it's going to be 0ÉF (-18ÉC)
or above. Do not use other viscosity grade oils, such as
SAE 10W-40 or SAE 20W-50 under any conditions.
Notice:Use only engine oil with the American
Petroleum Institute Certi®ed For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
GM Goodwrench
žoil meets all the requirements for
your vehicle.
If you are in an area of extreme cold, where the
temperature falls below-20ÉF (-29ÉC), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Don't add anything to your oil. The recommended oils
with the starburst symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil
(GM Oil Life System)
Your vehicle has a computer system that lets you know
when to change the engine oil and ®lter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system to work
properly, you must reset the system every time the oil is
changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is necessary.
A CHANGE ENG OIL light will come on. Change your oil
as soon as possible within the next two times you stop for
fuel. It is possible that, if you are driving under the best
conditions, the oil life system may not indicate that an oil
change is necessary for over a year.
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Part A: Scheduled Maintenance
Services
This part contains engine oil scheduled maintenance
which explains the engine oil life system and how
it indicates when to change the engine oil and ®lter.
Also, listed are scheduled maintenance services which
are to be performed at the mileage intervals speci®ed.
Using Your Maintenance Schedule
We at General Motors want to help you keep your
vehicle in good working condition. But we don't know
exactly how you'll drive it. You may drive very short
distances only a few times a week. Or you may drive
long distances all the time in very hot, dusty weather.
You may use your vehicle in making deliveries. Or
you may drive it to work, to do errands or in many
other ways.
Because of all the different ways people use their
vehicles, maintenance needs vary. You may need more
frequent checks and replacements. So please read
the following and note how you drive. If you have any
questions on how to keep your vehicle in good condition,
see your dealer.This part tells you the maintenance services you should
have done and when to schedule them.
When 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.
The proper ¯uids and lubricants to use are listed in Part
D. 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.
This schedule is for vehicles that:·carry passengers and cargo within recommended
limits. You will ®nd these limits on your vehicle's
Certi®cation/Tire label. See
Loading Your Vehicle on
page 4-47.
·are driven on reasonable road surfaces within legal
driving limits.
·are driven off-road in the recommended manner.
See
Off-Road Driving with Your Four-Wheel-Drive
Vehicle on page 4-15.
·use the recommended fuel. SeeGasoline Octane
on page 5-4
.
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