1995 CHEVROLET SUBURBAN brake fluid

Off-Road Driving with Your Four-wheel Drive
Vehicle
This off-road guide is for vehicles that have four-wheel drive.
Also, see “Anti-Lock Brakes”
in the Index.
If your vehicle doesn’t have four-wheel drive, you shouldn’t drive off-road
unless you’re on a level, solid surface.
Off-road driving can be great
fun. But it does have some definite hazards.
The greatest
of these is the terrain itself.
“Off-roading” means you’ve left the great North American road system
behind. Traffic lanes aren’t marked. Curves aren’t banked. There are no
road signs. Surfaces can be slippery, rough, uphill or downhill. In short,
you’ve gone right back to nature.
Off-road driving involves some new
skills. And that’s why it’s very
important that you read this guide. You’ll find many driving tips and
suggestions. These will help make your off-road driving safer and more
enjoyable.
Before You Go Off-Roading
There are some things to do before you go out. For example, be sure to have
all necessary maintenance and service work done. Check to make sure all
underbody shields (if
so equipped) are properly attached. Be sure you read
all
the information about your four-wheel drive vehicle in this manual. Is
there enough fuel? Is the spare tire fully inflated? Are the fluid levels up
where they should be? What are
the local laws that apply to off-roading
where you’ll be driving? If you don’t know, you should check with law
enforcement people in the area. Will you be
on someone’s private land? If
so, be sure to get the necessary permission.
Loading Your Vehicle for Off-Road Driving
There are some important things to remember about how to load your
vehicle.
0 The heaviest things should be on the load floor and forward of your
0 Be sure the load is secured properly, so driving on the off-road terrain
rear axle. Put
heavier items as far forward as you can.
doesn’t toss things around.
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There is something about an easy stretch of road with the same scenery,
along with the hum
of the tires on the road, the drone of the engine, and the
rush of the wind against the vehicle that can make you sleepy. Don’t let it
happen to
you! If it does, your vehicle can leave the road in less than a
second,
and you could crash and be injured.
What can you do about highway hypnosis? First, be aware that it can
happen.
Then here are some tips:
0 Make sure your vehicle is well ventilated, with a comfortably cool
interior.
Keep your eyes moving. Scan the road ahead and to the sides. Check
your mirrors and your instruments frequently.
and take a nap, get some exercise, or both. For safety, treat drowsiness
If you get sleepy, pull off the road into a rest, service, or parking area
on the highway
as an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from driving in flat or
rolling terrain.
If you drive regularly in steep country, or if you’re planning to visit there,
here are some tips that can make your trips safer and more enjoyable. (See
“Off-Road Driving”
in the Index for information about driving off-road.)
0
0
Keep your vehicle in good shape. Check all fluid levels and also the
brakes, tires, cooling system and transmission. These parts can work
hard on mountain roads.
Know
how to go down hills. The most important thing to know is this:
let your engine
do some of the slowing down. Shift to a lower gear
when
you go down a steep or long hill.
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Trailer Brakes
If your trailer weighs more than 1,000 pounds (450 kg) loaded, then it needs
its own brakes
- and they must be adequate. Be sure to read and follow the
instructions for the trailer brakes
so you’ll be able to install, adjust and
maintain them properly.
Your trailer brake system can tap into your vehicle’s hydraulic brake system,
but consider the following:
Don’t tap into your vehicle’s brake system if the trailer’s brake system
will use more than
0.02 cubic inch (0.3~~) of fluid from your vehicle’s
master cylinder. If it
does, both braking systems won’t work well. You
could even lose your brakes.
0 Will the trailer brake parts take 3,000 psi (20 650 kPa) of pressure? If
not, the trailer brake system must not be used with your
vehicle.
If everything checks out this far, make the brake tap at the port on the
master cylinder that sends the fluid to the rear brakes. But don’t
use copper
tubing for this. If you do, it will bend and finally break off. Use steel brake
tubing.
Driving with a Trailer
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Maintenance When Trailer Towing
Your vehicle will need service more often when you’re pulling a trailer. See
the Maintenance Schedule for more on this. Things that are especially
important
in trailer operation are automatic transmission fluid (don’t
overfill), engine oil, axle lubricant, belt, cooling system, an\
d brake
adjustment. Each
of these is covered in this manual, and the Index will help
you find them quickly. If you’re trailering, it’s a good idea to review these
sections before you start your trip.
Check periodically to see
that all hitch nuts and bolts are tight.
Trailer Lighting Systems Wiring
See “Trailer Wiring Harness” in the Index.
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Wait at least 30 minutes before checking the transmission fluid level if you
have been driving:
0 When outside temperatures are above 90°F (32°C j,
At high speed for quite a while.
In heavy traffic - especially in hot weather.
0 While pulling a trailer.
To get the right reading, the fluid should be at normal operating
temperature, which
is 180°F to 200°F (82°C to 93°C).
To check transmission fluid hot: Get the vehicle warmed up by driving
about
15 miles (24 km) when outside temperatures are above 50°F (1 0°C).
If it's colder than 50°F (10"C), drive
the vehicle in DRIVE (D) until the
engine temperature gage moves and then remains steady for ten minutes.
Then follow the
hot check procedures.
To check transmission fluid cold: A cold check is made after the vehicle
has been sitting for eight hours
or more with the engine off and is used only
as
a reference. Let the engine run at idle for five minutes if outside
temperatures are 50°F (10°C) or more. If it's colder than 50°F (IO'C), you
may have to idle
the engine longer. Should the fluid level be low during a
cold check,
you must perform a hot check before adding fluid. This will
give you
a more accurate reading of the fluid level.
lo check the fluid hot or cold
0 Park your vehicle on a level place. Keep the engine running.
With the parking brake applied, place the shift lever in PARK (P).
With your foot on the brake pedal, move the shift lever through each
gear range, pausing
for about three seconds in each range. Then,
position
the shift lever in PARK (P).
Let the engine run at idle for three minutes or more.
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Power Steering Fluid
How To Check Power Steering Fluid
When the engine compartment is cool, unscrew the cap and wipe the
dipstick
with a clean rag. Replace the cap and completely tighten it. Then
remove the cap again
and look at the fluid level on the dipstick.
The level should be at the FULL COLD mark. Add enough fluid to bring
the level up
to the mark.
A fluid
loss in this system could indicate a problem. Have the system
inspected and repaired.
What to Add
Refer to the Maintenance Schedule to determine what kind of fluid to use.
See “Recommended Fluids and Lubricants”
in the Index.
I
I NOTICE:
When adding power steering fluid or making a complete fluid
change, always use the proper fluid. Failure to use the proper\

fluid can cause leaks and damage hoses and seals.
Hydro-Boost Brake System (Hydraulic Pump)
The power steering pump is also used as the Hydro-boost pump. Refer to
“Power Steering System” in this section when checking fluid level or
adding fluid.
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Brakes
Brake Master Cylinder
Your brake master cylinder is here. It is filled with DOT-3 brake fluid.
I L m
There are only two reasons why the brake fluid level in your master cylinder
might
go down. The first is that the brake fluid goes down to an acceptable
level during normal brake lining wear. When new linings are put
in, the
fluid level goes back up. The other reason is that fluid is leaking out of the
brake system.
If it is, you should have your brake system fixed, since a leak
means that sooner or later your brakes won’t
work well, or won’t work at
all.
So, it isn’t a good idea to “top off” your brake fluid. Adding brake fluid
won’t correct a leak.
If you add fluid when your linings are worn, then
you’ll have
too much fluid when you get new brake linings. You should add
(or remove) brake fluid, as necessary, only when work is done on
the brake
hydraulic system.
I
Refer to the Maintenance Schedule to determine when to check your brake
fluid. See “Periodic Maintenance Inspections’’
in the Index.
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To Check Brake Fluid
You can check the brake fluid without taking off the cap. Just look at the
windows
on the brake fluid reservoir. The fluid levels should be above MIN.
If
they aren’t, have your brake system checked to see if there is a leak.
After work
is done on the brake hydraulic system, make sure the levels are
above
MIN and below the top of each window.
What to Add
When you do need brake fluid, use only DOT-3 brake fluid - such as
Delco Supreme 1 1 @ (GM Part No. 1052535). Use new brake fluid from a
sealed container only, and always clean the brake fluid reservoir cap before
removing it.
NOTICE:
Don’t let someone put in the wrong kind of fluid. For
example, just a few drops of mineral-based oil, such
as engine
oil, in your brake system can damage brake system parts so
badly that they’ll have to be replaced.
Brake fluid can damage paint, so be careful not to spill brake
fluid on your vehicle. If you do, wash it off immediately. See
“Appearance Care” in the Index.
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