2008 CHEVROLET KODIAK maintenance

Automatic Transmission Fluid
When to Check
A good time to check your automatic transmission fluid
level is when the engine oil is checked. See your
Allison Automatic Transmission Operator’s Manual to
find out when to change your transmission fluid
and filters.
How to Check and What to Use
The Allison Automatic Transmission Operator’s Manual
that came with the vehicle shows how to check the
automatic transmission fluid and what fluid to use.
Automatic Transmission External Filter
Your automatic transmission filter requires periodic
replacement.
Consult the Allison Automatic Transmission Operator’s
Manual that came with the vehicle for proper change
intervals.
Manual Transmission Fluid
When to Check
A good time to have it checked is when the engine oil is
checked. Refer to the Maintenance Schedule to find
out when to check and change your manual
transmission fluid. SeeScheduled Maintenance on
page 6-5.
How to Check and What to Use
Check the fluid level only when your engine is off, the
vehicle is parked on a level place, and the transmission
is cool enough for you to rest your fingers on the
transmission case.
To check the transmission fluid level, do the following:
1. Remove the filler plug.
2. Check to be sure that the lubricant level is up to the
bottom of the fill opening. On heavy duty
transmissions, an inch of oil level equals about one
gallon of fluid.
3. If the fluid level is good, reinstall the plug and be
sure it is fully seated. If the fluid level is low, add
more fluid as described in the next steps. Refer to
the Maintenance Schedule to determine what kind
of fluid to use. SeePart C: Recommended Fluids and
Lubricants on page 6-31.
5-43

How to Add Fluid
To add transmission fluid, do the following:
1. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only enough
fluid to bring the fluid level up to the bottom of
the fill opening. Refer to the Maintenance
Schedule to determine the proper fluid to use.
SeePart C: Recommended Fluids and Lubricants
on page 6-31.
3. Reinstall the filler plug. Be sure the plug is fully
seated.
Engine Coolant (Caterpillar®Diesel
Engines)
If your vehicle has a Caterpillar®diesel engine, see the
Caterpillar®Diesel Engine Operation & Maintenance
Manual provided with your vehicle to find out what to
add, as well as when and how to service your cooling
system.
Engine Coolant (Gas and
DURAMAX
®/Isuzu 7.8L L6 Engines)
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for five years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating, seeEngine Overheating on
page 5-48.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
•Give freezing protection down to−34°F (−37°C).
•Give boiling protection up to 265°F (129°C).
•Protect against rust and corrosion.
•Help keep the proper engine temperature.
•Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-44

Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Engine Fan
B. Coolant Surge Tank
If your vehicle has a Caterpillar
®diesel engine, see the
Caterpillar®Diesel Engine Operation and Maintenance
Manual provided with your vehicle.
If the coolant inside the coolant surge tank is boiling, do
not do anything else until it cools down. The vehicle
should be parked on a level surface.The coolant level should
be at the FULL COLD
mark or higher. If it is not,
you may have a leak at
the pressure cap or in the
radiator hoses, heater
hoses, radiator, water
pump, or somewhere else
in the cooling system.
5-50

4. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the engine
cooling fan.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches slightly above the FULL
COLD mark.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not fully engaged. This improves
fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside
temperatures, the fan speed increases when the clutch
engages. So you may hear an increase in fan noise. This
is normal and should not be mistaken as the transmission
slipping or making extra shifts. It is merely the cooling
system functioning properly. The fan will slow down when
additional cooling is not required and the clutch
disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
Power Steering Fluid
SeeScheduled Maintenance on page 6-5to determine
when to check your power steering fluid.
5-54

Brakes
Brake Fluid
If your vehicle has
hydraulic brakes, there is a
brake master cylinder in
the engine compartment
on the driver side of the
vehicle.
Refer to the Maintenance Schedule to determine when
to check the brake fluid.
{CAUTION:
Do not add brake uid before you check the
level. If you do, you could get too much brake
uid. Brake uid could spill on the hot engine
and it can catch re. You could be burned and
your vehicle could be damaged. See “Checking
Brake Fluid” in this section.
Checking Brake Fluid
Apply the brake pedal several times with the ignition off.
The brake fluid reservoir is in the engine compartment
on the driver side of the vehicle. Clean one of the
reservoir caps and the area around the cap, and
remove it.
The fluid level should be
even with the bottom ring
of the filler opening. If it is
low, add enough fluid to fill
the reservoir to the proper
level.
5-57

What to Add
Use the proper fluid listed in the Maintenance Schedule.
Use new brake fluid from a sealed container only.
Always clean the brake fluid reservoir cap/cover and the
area around the cap/cover before removing it. This
helps keep dirt from entering the reservoir.
{CAUTION:
With the wrong kind of uid in the brake
hydraulic system, the brakes might not work
well. This could cause a crash. Always use the
proper brake uid.Notice:
Using the wrong uid can badly damage brake
hydraulic system parts. For example, just a
few drops of mineral-based oil, such as engine
oil, in the brake hydraulic system can damage
brake hydraulic system parts so badly that they
will have to be replaced. Do not let someone
put in the wrong kind of uid, and do not use
DOT-5 silicone brake uid.
If you spill brake uid on your vehicle’s painted
surfaces, the paint nish can be damaged. Be
careful not to spill brake uid on your vehicle. If
you do, wash it off immediately. SeeWashing
Your Vehicle on page 5-97.
Four-Wheel Disc Brakes
(Hydraulic Only)
Your vehicle has four-wheel disc brakes.
Some driving conditions or climates can cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
the brakes.
Brake linings should always be replaced as complete
axle sets.
5-58

Hydraulic Brake Pads
Brake pad lining life will vary depending on vehicle
application, working environment, equipment
maintenance, and style of driving. The brake pad lining
wear rate has to be monitored for individual driving
habits — original equipment linings have mechanical
wear indicators to help with this. When you are down to
the last 10% of the brake lining, the brake lining wear
indicator will rub on the rotor, causing a scratching or
chirping sound. When you hear this sound, it is time to
service the brake pads. SeeScheduled Maintenance on
page 6-5.
Aftermarket brake linings might not meet the same
stringent requirements as the original equipment linings.
Using aftermarket brake linings can affect braking
performance, pedal feel, noise, and lining wear.
Air Brake Systems
If your vehicle has air brakes, it is important to get rid of
moisture in the system. Moisture will damage the
system if it is not removed daily.
There are two ways to do this. One is automatic through
the air brake vehicle’s air dryer with integral automatic
moisture ejector that purges air from the system through
a self-contained reservoir. The other way to drain
moisture from the air brake system is to manually activate
drain valves at each reservoir. Drain the air reservoirs
occasionally to be sure the air dryer is working properly.Drain the air brakes at full system pressure. To be sure
you are at full pressure, check the air pressure gage.
It should read at least 100 psi (692 kPa).
Air Dryer
If your vehicle has air brakes, it has an air dryer
mounted on the passenger side frame rail. This collects
and removes dirt, moisture, or other foreign matter
from the air prior to entering the brake system. The dryer
also acts as a moisture ejector. It automatically ejects
the moisture when the compressor cycles. The
purge tank has a manual drain valve that must be
drained every day. See “Air Brake Systems” for the
manual drain procedure.
The dryer has a filter that you need to change at
intervals. SeeScheduled Maintenance on page 6-5for
more about servicing this filter.
Electric Air Compressor
Your vehicle might have an electric air compressor. This
compressor is used to run options that require
pressurized air, such as an air horn or air seat.
The air compressor is used when vehicles do not have
an air brake system.
5-60

The air supply for this
system must be
maintained by releasing
the drain valve to eject any
moisture that could have
built up in the system.
It is recommended that this system be drained on a
weekly basis.Clutch Pedal Free Travel
If you have a V8 engine and a manual transmission, the
clutch will need adjustment when pedal free travel gets
down to about 1/4 inch (6 mm), as measured at the clutch
pedal pad. You should have 1 1/2 to 2 inches
(38 to 51 mm) of clutch pedal free travel.
If the clutch ever needs service, be sure to use only
approved clutch replacement parts.
Chassis Lubrication
Your Maintenance Schedule provides all of the required
chassis lubrication intervals and identifies proper
lubricants to use. Be sure to see the Maintenance
Schedule before performing any chassis lubrication
service. To determine location of chassis lubrication
items, use the following charts.
5-61