1994 CHEVROLET SUBURBAN maintenance

Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how often to check the
lubricant and when to change
it. See “Scheduled Maintenance Services” in
the Index.
How to Check Lubricant
If the level is below
the bottom of the filler
plug hole, you’ll need
to add some lubricant.
If the differential is at
operating temperature
(warm), add enough
lubricant to raise the level
to the bottom of
the filler plug hole.
If the differential is cold, add enough lubricant to raise the level to
1/2 inch
(12 mm) below the filler plug hole.
What to use
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
Engine Coolant
The following explains your cooling system and how to add coolant when it
is low. If you have a problem with engine overheating, see “Engine
Overheating”
in the Index.
The proper coolant for your vehicle will:
Give freezing protection down to -20°F (-29”C), or -34°F (-37°C) in
Give boiling protection up to 258°F (1 25°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Canada
and for vehicles with the cold climate option.
Let the warning lights and gages work as they should.
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How To Check Power Steering Fluid
l
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.
0 When the engine
compartment is
hot, the level
should
be at the
FULL mark.
When the engine
compartment is
cool, the
level
should be at the
FULL COLD
mark.
Whaf fo Add
Refer to the Maintenance Schedule to determine what kind of fluid to use.
See “Recommended Fluids and Lubricants” in the Index.
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.
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Brakes
Brake Master Cylinder
4 Your brake master
cylinder
is here. It is
filled with
DOT-3
brake fluid.
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.
Refer to the Maintenance Schedule to determine when to check your brake
fluid. See “Periodic Maintenance Inspections” in the Index.
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Replacing Brake System Parts
The braking system on a modern 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. Vehicles we design and test have top-quality
GM brake parts in
them, as your vehicle does when it is new. When you replace parts of your
braking system
- for example, when your brake linings wear down and
you have to have new ones put
in - be sure you get new genuine GM
replacement parts. If you don’t, 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’ve come to expect can change
in many
other ways
if someone puts in the wrong replacement brake parts.
Other Maintenance Items
Front Suspension and Steering Linkage
Your maintenance schedule will tell you how often to lubricate the fittings.
See “Recommended Fluids and Lubricants” in the Index for the proper
lubricant to use.
Front Wheel Bearing
Your vehicle has front wheel bearings that must be cleaned and repacked.
Your maintenance schedule will tell you how often this must be done.
Front Shock Absorbers
The front shock absorbers of your vehicle do many things. They help the
vehicle ride smoothly and also control the travel of the suspension system.
When the shock absorbers are serviced, any replacement shock absorbers
must be the same as the original equipment shock absorbers
in both
extended length
and strength.
I NOTICE:
If you use shock absorbers that are not the same as the original
shock absorbers, the shock absorbers or suspension system
could be damaged.
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Fluid Leak Check
After the vehicle has been parked for a while, inspect the surface under the
vehicle for water, oil, fuel or other fluids. Water dripping from the air
conditioning system after it has been used is normal. If you notice fuel leaks
or fumes, the causes should be found and corrected at once.
Lubrication
Accelerator Control System
Your maintenance schedule will tell you how often the accelerator linkage
pivot points must be lubricated. See “Recommended Fluids and Lubricants”
in
the Index for the proper lubricant to use.
Accelerator cables and cruise control cables should not be lubricated. Any
cables that are worn or
are hard to pull should be replaced.
Hood Latches and Hood Hinge
Your maintenance schedule will tell you how often to lubricate the hood
latch and hood hinge assembly. See the Index under “Recommended Fluids
and Lubricants” for the proper lubricant to use.
Propeller Shaft Slip Splines
See your maintenance schedule to find out how often the slip splines must
be lubricated. See “Recommended Fluids and Lubricants” in the Index for
the proper lubricant to use.
Constant Velocity Joints
See your maintenance schedule to find out how often the constant velocity
joints must be lubricated. See “Recommended Fluids and Lubricants” in the
Index for the proper lubricant to use.
Normal
use of your vehicle will cause metal to metal wear at some points on
the cab and body if they are not lubricated.
For exposed surfaces, such
as door checks, door lock bolts, lock striker plates,
dovetail bumper wedges, etc., a thin
film of engine oil should be applied.
The seat adjusters and seat track should be lubricated
with chassis grease.
Door weather strips and rubber hood bumpers should be lightly coated with
a rubber lubricant.
Never use too much of any lubricant and be sure to wipe up any extra
lubricant when you are finished.
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Your maintenance schedule will tell you how often to lubricate these items.
See “Recommended Fluids and Lubricants” in the Index for the proper
lubricant to use.
Lock Cylinders
To be sure your locks operate properly, they must be lubricated. Your
vehicle’s maintenance schedule will tell you how often to lubricate them.
See “Recommended Fluids and Lubricants” in the Index for the proper
lubricant to use.
You should not use penetrating oils because they could wash out the factory
installed lubricant and cause the lock to bind. De-icers which contain
alcohol could
also wash away the lubricant, so be sure to lubricate the lock
after using a de-icer of this type.
Tailgate Handle
The tailgate handle pivot points on your vehicle should be lubricated to keep
it working smoothly.
Your maintenance schedule will tell you how often to lubricate the handle.
See “Recommended Fluids and Lubricants” in the Index for the proper
lubricant to use.
Battery
Every new GM vehicle has a Delco Freedom@ battery. You never have to
add water to one of these. When it’s time for a new battery, we recommend
a Delco Freedom@ battery. Get one that has the catalog number shown on
the original battery’s label.
Vehicle Storage
If you’re not going to drive your vehicle for 25 days or more, take off the
black, negative
(-) cable from the battery. This will help keep your battery
from running down.
Contact your dealer to learn how to prepare your vehicle for longer storage
periods.
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Special Tire lnflation
If you have 16 inch tires on your vehicle, and:
- You’ll be driving for very long at speeds of 66 mph (105 kdh) to
75 mph (120 km/h) where legal, inflate tires to 10 psi (70 kPa)
more than the recommended cold inflation pressures.
- You’ll be driving for very long at speeds of 76 mph ( 120 kdh) to
85 mph (1 35 kdh) where legal, cold inflation pressures should be
increased by
10 psi (70 kPa) and you must also reduce axle load
capacity by 10%.
Do not drive over 85 mph (135 km/h) even if
it’s legal.
Inflation pressures should never exceed 10 psi (70 kPa) above the
inflation specified for the maximum load
of the tire.
Tire lnspection and Rotation
To make your tires last longer, have them inspected and rotated at the
mileages recommended
in the Maintenance Schedule. See “Scheduled
Maintenance Services” in the Index.
FRT FRT
Use this rotation
pattern.
If your vehicle has front tires with different load ratings or tread designs
(such
as all season vs. on/off road) than the rear tires, don’t rotate your tires
front
to rear.
After the tires have been rotated, adjust the front and rear inflation pressure
as shown on the Certificationmire label. Make certain that all wheel nuts are
properly tightened. See “Wheel Nut Torque” in the Index.
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Weatherstrips
Silicone grease on weatherstrips will make them last longer, seal better, and
not stick or squeak. Apply silicone grease with a clean cloth at least every
six months. During very cold, damp weather more frequent application may
be required. (See “Recommended Fluids
& Lubricants’’ in the Index.)
Sheet Metal Damage
If your vehicle is damaged and requires sheet metal repair or replacement,
make sure the body repair shop applies anti-corrosion material to the parts
repaired or replaced to
restore corrosion protection.
Foreign Material
Calcium chloride and other salts, ice melting agents, road oil and tar, tree
sap, bird droppings, chemicals from industrial chimneys, and other foreign
matter can damage your vehicle’s finish if they remain on painted surfaces.
Use cleaners that are marked safe for painted surfaces to remove foreign
matter.
Finish Damage
Any stone chips, fractures or deep scratches in the finish should be repaired
right away. Bare metal will corrode quickly and may develop into a major
repair expense.
Minor chips and scratches can be repaired with touch-up materials available
from your dealer or other service outlets. Larger areas of finish damage can
be corrected
in your dealer’s body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust control can collect on
the underbody. If these are not removed, accelerated corrosion (rust) can
occur
on the underbody parts such as fuel lines, frame, floor pan, and
exhaust system even though they have corrosion protection.
At least every spring,
flush these materials from the underbody with plain
water. Clean
any areas where mud and other debris can collect. Dirt packed
in closed areas of the frame should be loosened before being flushed. Your
dealer or an underbody vehicle washing system can do this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create a chemical fallout.
Airborne pollutants can fall upon and attack painted surfaces on your
vehicle. This damage can take two
forms: blotchy, ringlet-shaped
discolorations, and small irregular dark
spots etched into the paint surface.
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