3. Refill with prediluted coolant as soon
as possible.
Water alone, without prediluted coolant,
can cause engine damage from corrosion,
overheating or freezing.
Do not use the following as a coolant
substitute:
• Alcohol.
• Methanol.
• Brine.
• Any coolant mixed with alcohol or
methanol antifreeze.
Alcohol and other liquids can cause engine
damage from overheating or freezing.
Do not add extra inhibitors or non-specified
additives to the coolant. These can be
harmful and compromise the corrosion
protection of the coolant.
Engine and Secondary Cooling
System Refill Procedure
The following procedure should be used
when refilling the engine or secondary
cooling systems after it has been drained
or become extremely low:
1. Before you remove the cap, turn the engine off and let it cool.
2. When the engine is cool, wrap a thick cloth around the cap. Slowly turn cap
counterclockwise until pressure begins
to release.
3. Step back when the pressure releases.
4. When you are sure that all the pressure
has been released, use the cloth to turn
the cap counterclockwise and then
remove it.
5. Slowly add prediluted engine coolant to the coolant reservoir until the
coolant level is within the minimum
and maximum range as listed on the
reservoir.
6. Reinstall the pressure relief cap. 7. Start and run the engine at 2000 rpm
for 2 minutes.
8. Shut engine off, and remove the pressure relief cap as previously
outlined.
9. If required, add prediluted engine coolant to the coolant reservoir until
the coolant level is within the minimum
and maximum range as listed on the
reservoir.
10. Engine cooling system: Repeat steps
5 through 9 until the coolant level has
stabilized (is no longer dropping after
each step) and the upper radiator
hose at the radiator is warm to the
touch (indicating that the engine
thermostat is open and coolant is
flowing through the radiator).
11. Check the secondary cooling system.
Repeat steps 1 through 10 until the
coolant level has stabilized (is no
longer dropping after each step) and
the lower passenger side of the
secondary radiator is warm to the
touch (indicating secondary
thermostat is open and coolant is
flowing through the entire system).
12. Check the coolant level in both systems before you drive your vehicle
the next few times.
13. If necessary, add prediluted engine coolant to the coolant reservoirs until
the coolant level is within the
minimum and maximum range as
listed on the reservoir. After any
coolant has been added, check the
coolant concentration.
Recycled Coolant
We do not recommend the use of recycled
coolant as an approved recycling process
is not yet available.
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inspection and keep to instructions
provided by the service manual.
Hydraulic brake systems are
power-assisted. There is a great
reduction in braking capabilities
without engine assist.
• Proper fluid level. The level should be
at the bottom edge of the ring on each
reservoir fill port. Do not fill the master
cylinder to the top of the reservoir. If
fluid level requires attention to
maintain a proper master cylinder level,
this is an indication of either severe
operation (pad wear) or fluid leakage.
A more frequent and thorough brake
inspection is required.
• Brake lines, hoses and fittings. Repair
or replace brake line tubes, hoses or
fittings as required. Inspect these
components every 4,000 mi
(6,000 km) for the following.
• Lines for kinks, dents, corrosion or
rupture.
• Hoses for abrasions, kinks, soft
spots or rupture, collapse, cracks,
twists or loose frame supports.
When replacing a hose, be sure
there is adequate clearance to the
hose to avoid an abrasion to the
new hose.
• All connections for leaks.
Driveline Parking Brake WARNING: Use wheel chocks and
exercise caution when inspecting under
the vehicle. A vehicle roll-away could
result in property damage, personal injury
or death.
A qualified technician should adjust the
parking brake and keep to the instructions
in the service manual. AXLE INSPECTION
Front Axle
Maintaining the front axle alignment to
specifications is very important. A qualified
technician should check and maintain the
alignment.
Regular inspections should include:
•
Toe-in inspection and adjustment (if
necessary), particularly with radial
tires.
• Checking for proper tightness of axle
mounting U-bolt nuts, attaching or
mounting bolts and nuts.
• Checking the axle for damage, binding,
worn parts and adequate lubrication.
• Checking the kingpins for excessive
wear. Also, perform this check during
other scheduled maintenance, for
example as tire rotation or service,
wheel bearing service and alignment.
See the workshop manual for proper
procedures.
Toe-in
It is essential to maintain correct toe-in
and tire pressure for optimum tire wear.
Inspecting steer axle tires in the first
3,000– 10,000 mi (5,000– 16,000 km)
generally shows if tires are wearing
normally.
Rapid outside shoulder wear on both tires
indicates too much toe-in.
Rapid inside shoulder wear on both tires
indicates too much toe-out.
In P&D-type service, there can be a
left-to-right steer tire tread life differential
up to 40% depending on routes and other
variables.
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Follow the tire manufacturer's
recommended cold inflation pressure for
the tire size, load range (ply rating) and
steer axle loading typical for their operation
(each steer axle tire equals ½ steer axle
loading).
Special applications may warrant a setting
based on experience with the type of tire
operating loads and conditions. Radial tires
are more sensitive to toe-in setting than
bias ply tires. Fine tuning school bus
alignment to line-haul truck standards
does not drastically improve tire tread life.
STEERING SYSTEM
INSPECTION
WARNING: Failure to maintain the
steering system in proper condition can
cause reduced steering ability resulting
in property damage, personal injury or
death.
Note: Have any steering problems
immediately corrected by a qualified service
technician.
Ask your service technician to examine the
steering mechanism. Only minor
adjustments may be necessary.
Regular inspections should include:
• Checking the tie rod, drag link end
clamp bolts and ball joints for proper
tightness.
• Checking for installation and spread of
cotter pins and tightness of nuts at
both ends of the tie rod and drag link.
• Checking that the pitman arm (steering
arm at steering gear) mounting is tight
and locked. Check system for leaks or
hose chafing. Repair immediately, if
necessary. •
Maintaining proper steering gear and
power steering pump lubricant levels.
• Checking steering column joint bolts
and steering linkage, particularly for
body-to-chassis clearance.
Steering Column Joint Bolts
As a good maintenance practice, check
steering column joint bolt tightness every
60,000 mi (96,000 km)
or annually,
whichever occurs first. Do not overtighten
the bolts.
Hydraulic System
Whenever draining and refilling the power
steering's hydraulic system for any reason,
bleed air from the system before returning
the vehicle to service. Failure to bleed the
hydraulic system properly can result in
degradation of power system performance.
Consult an authorized dealer who is aware
of the proper procedures for filling and
bleeding the system.
SUSPENSION SYSTEM
INSPECTION
Note: Do not adjust air suspension height
to any setting other than the specified
setting. Altering the height setting changes
the driveline angle and may result in
unwarrantable component damage, such
as transmission component damage.
Verify drive axle air suspension height and
height control valve performance at engine
oil change intervals.
Periodically check:
• Condition of spring leaves for evidence
of fatigue, bending or breakage.
• Condition of suspension mounting
brackets and bushings.
• Torque rod mounting fasteners for
tightness.
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Note:
It is necessary to reset memory
features if you disconnect the battery
cables.
Brakes
• Make sure the brakes and parking brake
release fully.
Tires
• Maintain recommended air pressure.
Miscellaneous
• Make sure all linkages, cables, levers
and pins under your vehicle are covered
with grease to prevent rust.
• Move vehicles at least 25 ft (7.5 m)
every 15 days to lubricate working parts
and prevent corrosion.
Removing Vehicle From Storage
When your vehicle is ready to come out of
storage, do the following:
• Wash your vehicle to remove any dirt
or grease film build-up on window
surfaces.
• Check windshield wipers for any
deterioration.
• Check under the hood for any foreign
material that may have collected
during storage such as mice or squirrel
nests.
• Check the exhaust for any foreign
material that may have collected
during storage.
• Check tire pressures and set tire
inflation per the Tire Label.
• Check brake pedal operation. Drive
your vehicle
15 ft (4.5 m) back and
forth to remove rust build-up. •
Check fluid levels (including coolant,
oil and gas) to make sure there are no
leaks, and fluids are at recommended
levels.
• If you remove the battery, clean the
battery cable ends and check for
damage.
Contact an authorized dealer if you have
any concerns or issues.
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TIRE CARE
Glossary of Tire Terminology
*Tire label: A label showing the
original equipment tire sizes,
recommended inflation pressure
and the maximum weight the
vehicle can carry.
*
Tire Identification Number: A
number on the sidewall of each
tire providing information about
the tire brand and manufacturing
plant, tire size and date of
manufacture. Also referred to as
DOT code.
*
Inflation pressure: A measure
of the amount of air in a tire.
*
Standard load: A class of
P-metric or Metric tires designed
to carry a maximum load at set
pressure. For example: For
P-metric tires 35 psi (241 kPa) and
for Metric tires
36 psi (248 kPa).
Increasing the inflation pressure
beyond this pressure does not
increase the tire ’s load carrying
capability.
*
Extra load: A class of P-metric
or Metric tires designed to carry a
heavier maximum load at
42 psi
(290 kPa). Increasing the inflation
pressure beyond this pressure
does not increase the tire ’s load
carrying capability.
*
kPa: Kilopascal, a metric unit of
air pressure.
*
PSI: Pounds per square inch, a
standard unit of air pressure. *
Cold tire pressure: The tire
pressure when the vehicle has
been stationary and out of direct
sunlight for an hour or more and
prior to the vehicle being driven for
1 mi (1.6 km)
.
*
Recommended inflation
pressure: The cold inflation
pressure is found on the Safety
Compliance Certification Label,
located in the driver's door jam.
*
Bead area of the tire: Area of
the tire next to the rim.
*
Sidewall of the tire: Area
between the bead area and the
tread.
*
Tread area of the tire: Area of
the perimeter of the tire that
contacts the road when mounted
on the vehicle.
*Rim: The metal support (wheel)
for a tire or a tire and tube
assembly upon which the tire
beads are seated.
Information Contained on the
Tire Sidewall
Both United States and Canada
Federal regulations require tire
manufacturers to place
standardized information on the
sidewall of all tires. This
information identifies and
describes the fundamental
characteristics of the tire and also
provides a U.S. DOT Tire
Identification Number for safety
standard certification and in case
of a recall.
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Information on P Type Tires
P215/65R15 95H is an example of
a tire size, load index and speed
rating. The definitions of these
items are listed below. (Note that
the tire size, load index and speed
rating for your vehicle may be
different from this example.)
A.
P: Indicates a tire, designated
by the Tire and Rim Association,
that may be used for service on
cars, sport utility vehicles,
minivans and light trucks. Note:
If
your tire size does not begin with
a letter this may mean it is
designated by either the European
Tire and Rim Technical
Organization or the Japan Tire
Manufacturing Association. B.
215:
Indicates the nominal
width of the tire in millimeters
from sidewall edge to sidewall
edge. In general, the larger the
number, the wider the tire.
C. 65:
Indicates the aspect ratio
which gives the tire's ratio of
height to width.
D. R:
Indicates a radial type tire.
E. 15:
Indicates the wheel or rim
diameter in inches. If you change
your wheel size, you have to
purchase new tires to match the
new wheel diameter.
F. 95:
Indicates the tire's load
index. It is an index that relates to
how much weight a tire can carry.
Note: You may not find this
information on all tires because it
is not required by federal law.
G. H:
Indicates the tire's speed
rating. The speed rating denotes
the speed at which a tire is
designed to be driven for extended
periods of time under a standard
condition of load and inflation
pressure. The tires on your vehicle
may operate at different
conditions for load and inflation
pressure. These speed ratings may
need to be adjusted for the
difference in conditions. The
ratings range from
81– 186 mph
(130– 299 km/h). These ratings
are listed in the following chart.
Note: You may not find this
information on all tires because it
is not required by federal law.
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*Traction: The traction grades,
from highest to lowest are AA, A,
B, and C. The grades represent the
tire's ability to stop on wet
pavement as measured under
controlled conditions on specified
government test surfaces of
asphalt and concrete. A tire
marked C may have poor traction
performance.
*
Temperature: The temperature
grades are A (the highest), B and
C, representing the tire's
resistance to the generation of
heat and its ability to dissipate
heat when tested under controlled
conditions on a specified indoor
laboratory test wheel.
M. Maximum Inflation
Pressure:
Indicates the tire
manufacturers' maximum
permissible pressure or the
pressure at which the maximum
load can be carried by the tire. This
pressure is normally higher than
the vehicle manufacturer's
recommended cold inflation
pressure which can be found on
the Safety Compliance
Certification Label. The cold
inflation pressure should never be
set lower than the recommended
pressure on the vehicle label.
The tire suppliers may have
additional markings, notes or
warnings such as standard load
or radial tubeless. Additional Information
Contained on the Tire Sidewall
for LT Type Tires
Note:
Tire Quality Grades do not
apply to this type of tire. LT type tires have some additional
information beyond those of P
type tires; these differences are
described below.
A.
LT:
Indicates a tire, designated
by the Tire and Rim Association,
that is intended for service on light
trucks.
B. Load Range and Load
Inflation Limits:
Indicates the
tire's load-carrying capabilities
and its inflation limits.
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C.
Maximum Load Dual lb (kg)
at psi (kPa) cold: Indicates the
maximum load and tire pressure
when the tire is used as a dual;
defined as four tires on the rear
axle (a total of six or more tires on
the vehicle).
D. Maximum Load Single lb
(kg) at psi (kPa) cold:
Indicates
the maximum load and tire
pressure when the tire is used as
a single; defined as two tires
(total) on the rear axle.
Information on T Type Tires
T145/80D16 is an example of a
tire size.
Note: The temporary tire size for
your vehicle may be different from
this example. Tire Quality Grades
do not apply to this type of tire. T type tires have some additional
information beyond those of P
type tires; these differences are
described below:
A.
T:
Indicates a type of tire,
designated by the Tire and Rim
Association, that is intended for
temporary service on cars, sport
utility vehicles, minivans and light
trucks.
B. 145:
Indicates the nominal
width of the tire in millimeters
from sidewall edge to sidewall
edge. In general, the larger the
number, the wider the tire.
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