2003 Lexus GX470 service

IN CASE OF AN EMERGENCY
393
NOTICE
You must provide the Lexus Link operator with your
Lexus Link PIN (Personal Identification Number) or
personal security word, before they lock/unlock your
vehicle. However, the Lexus Link System will not be
able to lock or unlock your vehicle if it has been parked
for 48 hours or more after the ignition is turned off.
Upon subscription expiration, all Lexus Link services
(i.e. automatic notification, emergency call functions,
service call functions) are deactivated.
If you must break a window to get in, we suggest breaking the
smallest side window because it is the least expensive to
replace. Be extremely cautious to avoid glass cuts.

MAINTENANCE
395
MAINTENANCE REQUIREMENTS
Your Lexus vehicle has been designed to have fewer
maintenance requirements with longer service intervals to
save both your time and money. However, each regular
maintenance as well as day−to−day care is more important
than ever before to ensure smooth, trouble −free, safe, and
economical driving.
It is the owner’s responsibility to make sure the specified
maintenance, including general maintenance services, is
performed. Note that both the new vehicle and emission
control system warranties specify that proper maintenance
and care must be performed. See the “Owner’s Guide”,
“Owner’s Manual Supplement” or “Warranty Booklet” for
complete warranty information.
General maintenance
General maintenance items are those day −to−day care
practices that are important to your vehicle for proper
operation. It is the owner’s responsibility to ensure that the
general maintenance items are performed regularly.
These checks or inspections can be done either by yourself or
your Lexus dealer.
Scheduled maintenance
The scheduled maintenance items listed in the “Owner’s
Manual Supplement / Scheduled Maintenance” are those
required to be serviced at regular intervals. For details of your maintenance schedule, read the “Owner’s
Manual Supplement / Scheduled Maintenance”.
It is recommended that only genuine Lexus parts be used
for maintenance or for the repair of the emission control
system.
The owner may elect to use nonLexus supplied parts for
replacement purposes without invalidating the emission
control system warranty. However, use of replacement
parts which are not of equivalent quality may impair the
effectiveness of the emission control systems.
You may also elect to have maintenance, replacement, or
repair of the emission control devices and system
performed by any automotive repair establishment or
individual without invalidating this warranty. See
“Owner’s Guide”, “Owner’s Manual Supplement” or
“Warranty Booklet” for complete warranty information.
Where to go for service?
Lexus
technicians are well −trained specialists and are kept up
to date with the latest service information through technical
bulletins, service tips, and in −dealership training programs.
They are well informed about the operation of all the systems
on your vehicle.
You can be confident that your Lexus dealer’s service
department performs the best job to meet the maintenance
requirements of your vehicle − reliably and economically.

MAINTENANCE
396Your copy of the repair order is proof that all required
maintenance has been performed for warranty coverage. If
any problems should arise with your vehicle while under
warranty,
your Lexus dealer will promptly take care of it. Again,
be sure to keep a copy of the repair order for any service
performed on your Lexus.
What about doityourself maintenance?
Many of the maintenance items are easy to do yourself, if you
have a little mechanical ability and a few basic automotive
tools. Simple instructions for how to perform them are
presented in Section 6.
If you are a skilled do −it− yourself mechanic, the Lexus service
manuals are recommended. Please be aware that
do−it−yourself maintenance can affect your warranty
coverage. See your “Owner’s Guide”, “Owner’s Manual
Supplement” or “Warranty Booklet” for the details.
GENERAL MAINTENANCE
Listed below are the general maintenance items that should be
performed at the intervals specified. It is recommended that
any problem you notice be brought to the attention of your
Lexus dealer or qualified service shop for their advice.
CAUTION
Make these checks only with adequate ventilation if you
run the engine.
Vehicle exterior
Items listed below should be performed from time to time,
unless otherwise specified.
Tire pressure
Check the pressure with a gauge every two weeks, or at least
once a month and adjust as shown on the tire pressure label.
See page 432 for additional information.
Tire surface
Check the tires carefully for cuts, damage or excessive wear.
See page 434 for additional information.
Wheel nuts
When checking the tires, make sure to check the nuts for
looseness. Tighten them if necessary.

MAINTENANCE
397
Tire rotation
Rotate the
tires according to the maintenance schedule. (For
scheduled maintenance information, please refer to the
“Owner’s Manual Supplement / Scheduled Maintenance”.)
See page 434 for additional information.
Fluid leaks
Check underneath for leaking fuel, oil, water or other fluid after
the vehicle has been parked for a while. If you smell fuel fumes
or notice any leak, have the cause found and corrected
immediately.
Doors and engine hood
Check that all side doors and back door, operate smoothly and
all latches lock securely. Make sure the engine hood
secondary latch secures the hood when the primary latch is
released.
Vehicle interior
Items listed below should be checked regularly, e.g. while
performing periodic services, cleaning the vehicle, etc.
Lights
Make sure the headlights, stop lights, tail lights, turn signal
lights, and other lights are working. Check headlight aim.
Service reminder indicators and warning buzzers
Check that all service reminder indicators and warning buzzers
function properly. Steering wheel
Check that it has the
specified free play. Be alert for changes
in steering condition, such as hard steering, excessive free
play or strange noise.
Seats
Check that all front seat controls such as seat adjusters,
seatback recliner, etc. operate smoothly. Check that the head
restraints move up and down smoothly and that the locks hold
securely in any latched position. For folding −up second and
third seats, and detachable third seat, check that the latches
lock securely.
Seat belts
Check that the seat belt system such as buckles, retractors
and anchors operate properly and smoothly. Make sure the
belt webbing is not cut, frayed, worn or damaged.
Accelerator pedal
Check the pedal for smooth operation and uneven pedal ef fort
or catching.
Brake pedal
Check the pedal for smooth operation and the proper
clearance and free play. Check the brake booster function.
Brakes
At a safe place, check that the brakes do not pull to one side
when applied.

MAINTENANCE
399
Brake fluid level
Make sure the brake fluid level is correct. See page 430 for
additional information.
Engine oil level
Check the level on the dipstick with the engine turned off and
the vehicle parked on a level spot. See page 419 for
additional
information.
Power steering fluid level
Check the level through the reservoir. The level should be in
the “HOT” or “COLD” range depending on the fluid
temperature. See page 431 for additional information.
Exhaust system
If you notice any change in the sound of the exhaust or smell
exhaust fumes, have the cause located and corrected
immediately. (See “Engine exhaust caution” on page 298.)
DOES YOUR VEHICLE NEED REPAIRING?
Be on the alert for changes in performance and sounds, and
visual tip −offs that indicate service is needed. Some important
clues are:
 Engine missing, stumbling, or pinging
 Appreciable loss of power
 Strange engine noises
 A fluid leak under the vehicle (However, water dripping from
the air conditioning after use is normal.)
 Change in exhaust sound (This may indicate a dangerous
carbon monoxide leak. Drive with the windows open and
have the exhaust system checked immediately.)
 Flat−looking tires, excessive tire squeal when cornering,
uneven tire wear
 Vehicle pulls to one side when driving straight on a level
road
 Strange noises related to suspension movement
 Loss of brake effectiveness, spongy feeling brake pedal,
pedal almost touches floors, vehicle pulls to one side when
braking
 Engine coolant temperature continually higher than normal

MAINTENANCE
400If you notice any of these clues, take your vehicle to your Lexus
dealer as soon as possible. It probably needs adjustment or
repair.
CAUTION
Do not continue driving with the vehicle unchecked. It
could result in serious vehicle damage and possibly
personal injury.
EMISSION INSPECTION AND
MAINTENANCE (I/M) PROGRAMS
Some states have vehicle emission inspection programs
which include OBD (On −Board Diagnostics) checks.
The OBD system monitors the operation of the emission
control system. When the OBD system determines that a
problem exists somewhere in the emission control system, the
malfunction indicator lamp comes on. In this case, your vehicle
may not pass the I/M test and need to be repaired. Contact
your Lexus dealer to service the vehicle.
Even if the malfunction indicator lamp does not come on, your
vehicle may not pass the I/M test as readiness codes have not
been set in the OBD system.
Readiness codes are automatically set during ordinary driving.
However, when the battery is disconnected or run down, the
codes are erased. Also, depending on your driving habits, the
codes may not be completely set.
Also, if the malfunction indicator lamp had come on recently
due to temporary malfunction such as a loose fuel tank cap,
your vehicle may not pass the I/M test.
The malfunction indicator lamp will go off after taking several
driving trips, but the error code in the OBD system will not be
cleared unless about 40 trips or more are taken.
If your vehicle does not pass the I/M test and the malfunction
indicator lamp does not come on, contact your Lexus dealer to
prepare the vehicle for re −testing.

SECTION 6 – 1
402
SERVICE PROCEDURES AND
SPECIFICATIONS
Introduction
Vehicle identification403
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Engine compartment overview 404
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Do−it−yourself service precautions 406
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Parts and tools 407
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INTRODUCTION
406
DOITYOURSELF SERVICEPRECAUTIONS
If you perform maintenance yourself, be sure to follow the
correct procedure given in this section.
You should be aware that improper or incomplete servicing
may result in operating problems.
Performing do −it−yourself maintenance during the warranty
period may affect your warranty coverage. Read the separate
Lexus Warranty statement for details and suggestions.
This Section gives instructions only for those items that are
relatively easy for an owner to perform. As explained in
Section 5, there are still a number of items that must be
performed by a qualified technician with special tools.
For information on tools and parts for do−it−yourself
maintenance, see “Parts and tools” on page 407.
Utmost care should be taken when working on your vehicle to
prevent accidental injury. Here are a few precautions that you
should be especially careful to observe:
CAUTION
 When the engine is running, keep hands, clothing,
and tools away from the moving fan and engine drive
belt. (Removing rings, watches, and ties is
advisable.)
 Right after driving, the engine compartment the
engine, radiator, exhaust manifold and power
steering fluid reservoir, etc. will be hot. So be
careful not to touch them. Oil, other fluids and spark
plugs may also be hot.
 If the engine is hot, do not remove the radiator cap or
loosen the drain plugs to prevent burning yourself.
 Do not smoke, cause sparks or allow open flames
around fuel or the battery. Their fumes are
flammable.
 Do not get under your vehicle with just the body jack
supporting it. Always use automotive jack stands or
other solid supports.
 Use eye protection whenever you work on or under
your vehicle where you may be exposed to flying or
falling material, fluid spray, etc.
 Be extremely cautious when working on the battery.
It contains poisonous and corrosive sulfuric acid.
 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.