2004 GMC ENVOY change time

Do not get too close to the vehicle you want to
pass while you are awaiting an opportunity. For one
thing, following too closely reduces your area of
vision, especially if you are following a larger
vehicle. Also, you will not have adequate space if
the vehicle ahead suddenly slows or stops.
Keep back a reasonable distance.
When it looks like a chance to pass is coming up,
start to accelerate but stay in the right lane and do
not get too close. Time your move so you will be
increasing speed as the time comes to move into the
other lane. If the way is clear to pass, you will have a
“running start” that more than makes up for the
distance you would lose by dropping back. And if
something happens to cause you to cancel your
pass, you need only slow down and drop back again
and wait for another opportunity.
If other vehicles are lined up to pass a slow vehicle,
wait your turn. But take care that someone is not
trying to pass you as you pull out to pass the slow
vehicle. Remember to glance over your shoulder and
check the blind spot.
Check your mirrors, glance over your shoulder, and
start your left lane change signal before moving out
of the right lane to pass. When you are far enough
ahead of the passed vehicle to see its front in your
inside mirror, activate your right lane change signal
and move back into the right lane. (Remember thatyour right outside mirror is convex. The vehicle you
just passed may seem to be farther away from you
than it really is.)
Try not to pass more than one vehicle at a time on
two-lane roads. Reconsider before passing the next
vehicle.
Do not overtake a slowly moving vehicle too rapidly.
Even though the brake lamps are not ashing, it may
be slowing down or starting to turn.
If you are being passed, make it easy for the
following driver to get ahead of you. Perhaps you can
ease a little to the right.
Loss of Control
Let us review what driving experts say about what
happens when the three control systems (brakes,
steering and acceleration) do not have enough friction
where the tires meet the road to do what the driver
has asked.
In any emergency, do not give up. Keep trying to steer
and constantly seek an escape route or area of less
danger.
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Getting Familiar with Off-Road Driving
It is a good idea to practice in an area that is safe
and close to home before you go into the wilderness.
Off-road driving does require some new and different
skills. Here is what we mean.
Tune your senses to different kinds of signals. Your
eyes, for example, need to constantly sweep the terrain
for unexpected obstacles. Your ears need to listen
for unusual tire or engine sounds. With your arms,
hands, feet and body, you will need to respond to
vibrations and vehicle bounce.
Controlling your vehicle is the key to successful off-road
driving. One of the best ways to control your vehicle
is to control your speed. Here are some things to keep
in mind. At higher speeds:
you approach things faster and you have less time
to scan the terrain for obstacles.
you have less time to react.
you have more vehicle bounce when you drive over
obstacles.
you will need more distance for braking, especially
since you are on an unpaved surface.
{CAUTION:
When you are driving off-road, bouncing and
quick changes in direction can easily throw
you out of position. This could cause you to
lose control and crash. So, whether you’re
driving on or off the road, you and your
passengers should wear safety belts.
Scanning the Terrain
Off-road driving can take you over many different kinds
of terrain. You need to be familiar with the terrain
and its many different features. Here are some things to
consider.
Surface Conditions:Off-roading can take you over
hard-packed dirt, gravel, rocks, grass, sand, mud, snow
or ice. Each of these surfaces affects the steering,
acceleration and braking of your vehicle in different ways.
Depending upon the kind of surface you are on, you may
experience slipping, sliding, wheel spinning, delayed
acceleration, poor traction and longer braking distances.
Surface Obstacles:Unseen or hidden obstacles can
be hazardous. A rock, log, hole, rut or bump can startle
you if you are not prepared for them. Often these
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obstacles are hidden by grass, bushes, snow or even
the rise and fall of the terrain itself. Here are some
things to consider:
Is the path ahead clear?
Will the surface texture change abruptly up ahead?
Does the travel take you uphill or downhill?
(There is more discussion of these subjects later.)
Will you have to stop suddenly or change direction
quickly?
When you drive over obstacles or rough terrain, keep a
rm grip on the steering wheel. Ruts, troughs or
other surface features can jerk the wheel out of your
hands if you are not prepared.
When you drive over bumps, rocks, or other obstacles,
your wheels can leave the ground. If this happens,
even with one or two wheels, you can not control the
vehicle as well or at all.
Because you will be on an unpaved surface, it is
especially important to avoid sudden acceleration,
sudden turns or sudden braking.
In a way, off-road driving requires a different kind of
alertness from driving on paved roads and highways.
There are no road signs, posted speed limits or
signal lights. You have to use your own good judgment
about what is safe and what is not.Drinking and driving can be very dangerous on any
road. And this is certainly true for off-road driving. At the
very time you need special alertness and driving
skills, your reexes, perceptions and judgment can be
affected by even a small amount of alcohol. You
could have a serious — or even fatal — accident if you
drink and drive or ride with a driver who has been
drinking. SeeDrunken Driving on page 4-2.Driving on Off-Road Hills
Off-road driving often takes you up, down or across a
hill. Driving safely on hills requires good judgment
and an understanding of what your vehicle can and can
not do. There are some hills that simply can not be
driven, no matter how well built the vehicle.
{CAUTION:
Many hills are simply too steep for any vehicle.
If you drive up them, you will stall. If you drive
down them, you can not control your speed.
If you drive across them, you will roll over.
You could be seriously injured or killed. If you
have any doubt about the steepness, do not
drive the hill.
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Adding a Snow Plow or Similar
Equipment
Your vehicle was neither designed nor intended for a
snow plow.
Notice:Adding a snow plow or similar equipment
to your vehicle can damage it, and the repairs would
not be covered by warranty. Do not install a snow
plow or similar equipment on your vehicle.
Towing a Trailer
{CAUTION:
If you do not use the correct equipment and
drive properly, you can lose control when you
pull a trailer. For example, if the trailer is too
heavy, the brakes may not work well — or even
at all. You and your passengers could be
seriously injured. Pull a trailer only if you have
followed all the steps in this section. Ask your
dealer for advice and information about towing
a trailer with your vehicle.Notice:Pulling a trailer improperly can damage
your vehicle and result in costly repairs that would
not be covered by your warranty. Always follow
the instructions in this section and check with your
dealer for more information about towing a trailer
with your vehicle.
To identify the trailering capacity of your vehicle, you
should read the information in “Weight of the Trailer” that
appears later in this section.
Trailering is different than just driving your vehicle by
itself. Trailering means changes in acceleration, braking,
handling, durability and fuel economy. Successful,
safe trailering takes correct equipment, and it has to be
used properly.
That’s the reason for this part. In it are many time-tested,
important trailering tips and safety rules. Many of
these are important for your safety and that of your
passengers. So please read this section carefully before
you pull a trailer.
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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 ENGINE 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. However, your engine oil and lter must be
changed at least once a year and at this time the system
must be reset. Your dealer has GM-trained people
who will perform this work using genuine GM parts and
reset the system. It is also important to check your
oil regularly and keep it at the proper level.
If the system is ever reset accidentally, you must
change your oil at 3,000 miles (5 000 km) since your
last oil change. Remember to reset the oil life system
whenever the oil is changed.
How to Reset the CHANGE ENGINE OIL
Light
The GM Oil Life System calculates when to change
your engine oil and lter based on vehicle use. Anytime
your oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where you change your oil prior to a
CHANGE ENGINE OIL light being turned on, reset the
system.
To reset the CHANGE ENGINE OIL light, do the
following:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal slowly
three times within ve seconds.
3. Turn the key to LOCK.
If the CHANGE ENGINE OIL light comes back on when
you start your vehicle, the engine oil life system has
not reset. Repeat the procedure.
For vehicles with the Driver Information Center, see
Driver Information Center (DIC) on page 3-50to reset
the system.
5-20

How to Inspect
To inspect the air cleaner/lter, remove the lter from
the vehicle and lightly shake lter to release loose dust
and dirt. If the lter remains “caked” with dirt, a new
lter is required.
To inspect or replace the lter, do the following:
1. Remove the screws on the engine cleaner/lter and
lift off the cover.
2. Remove the air cleaner/lter from the housing. Care
should be taken to dislodge as little dirt as possible.
3. Install the new engine air cleaner/lter.
4. Reinstall the cover and tighten the screws.
{CAUTION:
Operating the engine with the air cleaner/lter
off can cause you or others to be burned. The
air cleaner not only cleans the air, it helps to
stop ame if the engine backres. If it is not
there and the engine backres, you could
be burned. Do not drive with it off, and be
careful working on the engine with the air
cleaner/lter off.Notice:If the air cleaner/lter is off, a backre can
cause a damaging engine re. And, dirt can
easily get into your engine, which will damage it.
Always have the air cleaner/lter in place when you
are driving.
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission uid
level is when the engine oil is changed.
Change both the uid and lter every 50,000 miles
(83 000 km) if the vehicle is mainly driven under one or
more of these conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change the uid and lter every
100,000 miles (166 000 km).
5-22

Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your
vehicle was designed and tested with top-quality GM
brake parts. When you replace parts of your braking
system — for example, when your brake linings
wear down and you need new ones put in — be sure
you get new approved GM replacement parts. If you do
not, your brakes may no longer work properly. For
example, if someone puts in brake linings that are wrong
for your vehicle, the balance between your front and
rear brakes can change — for the worse. The braking
performance you have come to expect can change
in many other ways if someone puts in the wrong
replacement brake parts.
Battery
Your new vehicle comes with a maintenance free
ACDelco®battery. When it is time for a new battery, get
one that has the replacement number shown on the
original battery’s label. We recommend an ACDelco
®
battery. SeeEngine Compartment Overview on
page 5-12for battery location.Warning:Battery posts, terminals and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
Vehicle Storage
If you are not going to drive your vehicle for 25 days or
more, remove the black, negative (−) cable from the
battery. This will help keep your battery from running
down.
{CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
are not careful. SeeJump Starting on
page 5-43for tips on working around a battery
without getting hurt.
Contact your dealer to learn how to prepare your
vehicle for longer storage periods.
Also, for your audio system, seeTheft-Deterrent
Feature (RDS Radios) on page 3-116.
5-42

When rotating your tires, always use the correct rotation
pattern shown here.
After the tires have been rotated, adjust the front and
rear ination pressures as shown on the
Certication/Tire label or the Tire and Loading
Information label. Make certain that all wheel nuts are
properly tightened. See “Wheel Nut Torque” under
Capacities and Specications on page 5-115.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the vehicle.
In an emergency, you can use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if you need to, to
get all the rust or dirt off. See “Changing a Flat
Tire” in the Index.
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