engine TOYOTA TUNDRA 2003 1.G Workshop Manual

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If towing a trailer and cargo weigh-
ing over 907 kg (2000 lb.), it is
necessary to use a sway control
device with sufficient capacity. The
combination of the gross trailer
weight added to the total weight of
the vehicle, occupants and vehicle
cargo must never exceed a total of
the following.
5VZFE engine
Twowheel drive models 4173 kg (9200 lb.)
Fourwheel drive models
4309 kg (9500 lb.)
2UZFE engine
Without towing package 4536 kg (10000 lb.)
With towing package
5352 kg (11800 lb.)
Exceeding the maximum weight of
the trailer, the vehicle, or the ve-
hicle and trailer combination, can
cause an accident resulting in seri-
ous personal injuries.
Trailer hitch assemblies have differ-
ent weight capacities established by
the hitch manufacturer. Even though
the vehicle may be physically capa-
ble of towing a higher weight, the
operator must determine the maxi-
mum weight rating of the particular
hitch assembly and never exceed
the maximum weight rating speci-
fied for the trailerhitch. Exceeding
the maximum weight rating set by
the trailer hitch manufacturer can
cause an accident resulting in seri-
ous personal injuries.
The gross vehicle weight must not
exceed the Gross Vehicle Weight
Rating (GVWR) indicated on the
Certification Label. The gross ve-
hicle weight is the sum of weights
of the unloaded vehicle, driver, pas-
sengers, luggage, hitch and trailer
tongue load. It also includes the
weight of any special equipment
installed on your vehicle.
The load on either the front or rear
axle resulting from distribution of
the gross vehicle weight on both
axles must not exceed the Gross
Axle Weight Rating (GAWR) listed
on the Certification Label.

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Total trailer weight Tongue load
Tongue load
Total trailer weight 
100 = 15% (
∗
1)or
9to11%(∗ 2)
The trailer cargo load should be
distributed so that the tongue load
is 15% for weight distributing hitch
(
∗1) or 9 to 11% for weight carrying
hitch (∗ 2) of the total trailer weight,
not exceeding the maximum load of
the following.
Weight distributing hitch
5VZFE engine Twowheel drive modelsStandard cab models
353 kg (780 lb.)
Access cab models 340 kg (750 lb.)
Fourwheel drive models 340 kg (750 lb.)
2UZFE engine Twowheel drive models Without towing package
374 kg (825 lb.)
With towing package 497 kg (1095 lb.)
Fourwheel drive models Standard cab models Without towing package
381 kg (840 lb.)
With towing package 503 kg (1110 lb.)
Access cab models Without towing package 361 kg (795 lb.)
With towing package 483 kg (1065 lb.)Weight carrying hitch
5VZFE engineTwowheel drive modelsStandard cab models
236 kg (520 lb.)
Access cab models 227 kg (500 lb.)
Fourwheel drive models 227 kg (500 lb.)
2UZFE engine Twowheel drive models Without towing package
249 kg (550 lb.)
With towing package 331 kg (730 lb.)
Fourwheel drive models Standard cab models Without towing package
254 kg (560 lb.)
With towing package 336 kg (740 lb.)
Access cab models Without towing package 240 kg (530 lb.)
With towing package 322 kg (710 lb.)

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1 Trailer ball load rating
2 Ball diameter
3 Shank length
4 Shank diameter
TRAILER BALL
Follow these easy steps to properly deter-
mine the correct trailer ball for your ap-
plication:
1. Determine the correct trailer ball size for the trailer coupler. Most couplers
are stamped with the required trailer
ball size. The sizes you will most likely
find stamped on the coupler are:
Trailer class
Typical trailer ball size
III and IV2 5/16 in.
II2 in.
I1 7/8 in.
2. Select the appropriate trailer ball to match or exceed the gross trailer
weight rating of the trailer. The trailer
ball load rating should be printed on
the top of the ball.
3. When mounted in the ball mount, the threaded ball shank must protrude be-
yond the bottom of the lock washer
and nut at least 2 threads. The trailer
ball shank must be matched to the ball
mount hole diameter size.
NOTICE
Vehicles with 2UZFE engine (with
towing package)—Only use a ball
mount attachment specified for the
Toyota Tundra.

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BREAKIN SCHEDULE
Toyota recommends that you do not
tow a trailer with a new vehicle or a
vehicle with any new power train com-
ponent (engine, transmission, differen-
tial, wheel bearings, etc.) for the first
800 km (500 miles) of driving.
MAINTENANCE
If you tow a trailer, your vehicle will
require more frequent maintenance due
to the additional load. For this informa-
tion, please refer to the scheduled
maintenance information in the “Sched-
uled Maintenance Guide” or “Owner ’s
Manual Supplement”.
Retighten all fixing bolts of the towing
ball and bracket after approximately
1000 km (600 miles) of trailer driving.
PRETOWING SAFETY CHECK
Check that your vehicle remains level
when a loaded or unloaded trailer is
hitched. Do not drive if the vehicle has
an abnormal nose −up or nose −down
condition, and check for improper
tongue load, overload, worn suspension
or other possible causes.
Make sure the trailer cargo is securely
loaded so that it cannot shift.
Check that your rear view mirrors con-
form to any applicable federal, state/
provincial or local regulations. If not,
install the rear view mirrors required
for towing purposes.
TRAILER TOWING TIPS
When towing a trailer, your vehicle will
handle differently than when not tow-
ing. The three main causes of vehicle
trailer accidents are driver error, exces-
sive speed and improper trailer loading.
Keep these in mind when towing:
Before starting out, check operation of
the lights and all vehicle −trailer connec-
tions. After driving a short distance,
stop and recheck the lights and con-
nections. Before actually towing a trail-
er, practice turning, stopping and back-
ing with a trailer in an area away from
traffic until you learn the feel.
Backing with a trailer is difficult and
requires practice. Grip the bottom of
the steering wheel and move your hand
to the left to move the trailer to the
left. Move your hand to the right to
move the trailer to the right. (This pro-
cedure is generally opposite to that
when backing without a trailer). Also,
just turn the steering wheel a little at
a time, avoiding sharp or prolonged
turning. Have someone guide you when
backing to reduce the risk of an acci-
dent.
Because stopping distance may be in-
creased, vehicle −to −vehicle distance
should be increased when towing a
trailer. For each 16 km/h (10 mph) of
speed, allow at least one vehicle and
trailer length between you and the ve-
hicle ahead. Avoid sudden braking as
you may skid, resulting in jackknifing
and loss of control. This is especially
true on wet or slippery surfaces.
Avoid jerky starts or sudden accelera-
tion. If your vehicle has a manual
transmission, prevent excessive clutch
slippage by keeping engine rpm low
and not racing the engine. Always start
out in first gear.

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Avoid jerky steering and sharp turns.
The trailer could hit your vehicle in a
tight turn. Slow down before making a
turn to avoid the necessity of sudden
braking.
Remember that when making a turn,
the trailer wheels will be closer than
the vehicle wheels to the inside of the
turn. Therefore, compensate for this by
making a larger than normal turning
radius with your vehicle.
Crosswinds and rough roads will ad-
versely affect handling of your vehicle
and trailer, causing sway. Pay attention
to the rear from time to time to pre-
pare yourself for being passed by large
trucks or buses, which may cause your
vehicle and trailer to sway. If swaying
happens, firmly grip the steering wheel
and reduce speed immediately but
gradually. Never increase speed. Steer
straight ahead. If you make no extreme
correction with the steering or brakes,
the vehicle and trailer will stabilize.
Be careful when passing other ve-
hicles. Passing requires considerable
distance. After passing a vehicle, do
not forget the length of your trailer and
be sure you have plenty of room be-
fore changing lanes.
In order to maintain engine braking effi-
ciency, do not use fifth gear (manual
transmission) or overdrive (automatic
transmission).
Because of the added load of the trail-
er, your vehicle’s engine may overheat
on hot days (at temperatures over
30C [85 F]) when going up a long or
steep grade with a trailer. If the engine
coolant temperature gauge indicates
overheating, immediately turn off the air
conditioning (if in use), pull off the road
and stop in a safe spot. Refer to “If
your vehicle overheats” in Section 4.
Always place wheel blocks under both
the vehicle and trailer wheels when
parking. Apply the parking brake firmly.
Put the transmission in “P” (automatic)
or in first or reverse (manual). Avoid
parking on a slope with a trailer, but
if it cannot be avoided, do so only
after performing the following:
1. Apply the brakes and hold.
2. Have someone place wheel blocks un- der both the vehicle and trailer wheels.
3. When the wheel blocks are in place, release your brakes slowly until the
blocks absorb the load.
4. Apply the parking brake firmly.
5. Shift into first or reverse (manual) or “P” (automatic) and turn off the engine.

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When restarting out after parking on a
slope:
1. With the transmission in “P” position (automatic) or the clutch pedal de-
pressed (manual), start the engine.
(With an automatic transmission, be
sure to keep the brake pedal de-
pressed.)
2. Shift into gear.
3. Release the parking brake (also foot brake on automatic transmission ve-
hicles) and slowly pull or back away
from the wheel blo cks. Stop and apply
your brakes.
4. Have someone retrieve the blo cks.CAUTION
Do not exceed 72 km/h (45 mph) or
the posted towing speed limit,
whichever is lower. Because insta-
bility (swaying) of a towing vehicle
trailer combination usually in-
creases as the speed increases, ex-
ceeding 72 km/h (45 mph) may
cause loss of control.
Slow down and downshift before
descending steep or long downhill
grades. Do not make sudden down-
shifts.
Avoid holding the brake pedal down
too long or too frequently. This
could cause the brakes to overheat
and result in reduced braking effi-
ciency.
Improving fuel economy is easy—just take
it easy. It will help make your vehicle last
longer, too. Here are some specific tips
on how to save money on both fuel and
repairs:
Keep your tires inflated at the cor-
rect pressure. Underinflation causes
tire wear and wastes fuel. See Section
7 −2 for instructions.
Do not carry unneeded weight in
your vehicle. Excess weight puts a
heavier load on the engine, causing
greater fuel consumption.
Avoid lengthy warmup idling. Once
the engine is running smoothly, begin
driving—but gently. Remember, howev-
er, that on cold winter days this may
take a little longer.
Always keep the automatic transmis-
sion overdrive switch turned on.
Driving with the overdrive switch off
will reduce the fuel economy. (For de-
tails, see “Automatic transmission” in
Section 1 −6.)
Accelerate slowly and smoothly.
Avoid jackrabbit starts. Get into high
gear as quickly as possible.
How to save fuel and make
your vehicle last longer

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Avoid long engine idling. If you have
a long wait and you are not in traffic,
it is better to turn off the engine and
start again later.
Avoid engine lugging or overrev-
ving. Use a gear position suitable for
the road on which you are travelling.
Avoid continuous speeding up and
slowing down. Stop−and− go driving
wastes fuel.
Avoid unnecessary stopping and
braking. Maintain a steady pace. Try
to time the traffic signals so you only
need to stop as little as possible or
take advantage of through streets to
avoid traffic lights. Keep a proper dis-
tance from other vehicles to avoid sud-
den braking. This will also reduce wear
on your brakes.
Avoid heavy traffic or traffic jams
whenever possible.
Do not rest your foot on the clutch
or brake pedal. This causes premature
wear, overheating and poor fuel econo-
my.
Maintain a moderate speed on high-
ways. The faster you drive, the greater
the fuel consumption. By reducing your
speed, you will cut down on fuel con-
sumption.
Keep the front wheels in proper
alignment. Avoid hitting the curb and
slow down on rough roads. Improper
alignment not only causes faster tire
wear but also puts an extra load on
the engine, which, in turn, wastes fuel.
Keep the bottom of your vehicle free
from mud, etc. This not only lessens
weight but also helps prevent corro-
sion.
Keep your vehicle tunedup and in
top shape. A dirty air cleaner,
improper valve clearance, dirty plugs,
dirty oil and grease, brakes not
adjusted, etc. all lower engine
performance and contribute to poor fuel
economy. For longer life of all parts
and lower operating costs, keep all
maintenance work on schedule, and if
you often drive under severe
conditions, see that your vehicle
receives more frequent maintenance.
(For scheduled maintenance informa-
tion, please refer to the “Scheduled
Maintenance Guide” or “Owner ’s
Manual Supplement”.)
CAUTION
Never turn off the engine to coast
down hills. Your power steering and
brake booster will not function with-
out the engine running. Also, the
emission control system operates
properly only when the engine is run-
ning.

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IN CASE OF AN EMERGENCY
In case of an emergency
If your vehicle will not start 234
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
If your engine stalls while driving 237
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
If you cannot increase the engine speed 238
. . . . . . . . . . . . . . . . . . . . . .
If your vehicle overheats 238
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
If you have a flat tire 239
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . .
If your vehicle becomes stuck 251
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
If your vehicle needs to be towed 252
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
If you lose your keys 257
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . .
If you lose your remote keyless entry transmitter 258
. . . . . . . . . . . . . . .
SECTION 4

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Before making these checks, make sure
you have followed the correct starting pro-
cedure given in “How to start the engine”
in Section 3 and that you have sufficient
fuel.
If the engine is not turning over or is
turning over too slowly—
1. Check that the battery terminals are tight and clean.
2. If the battery terminals are O.K., switch on the interior light.
3. If the light is out, dim or goes out when the starter is cranked, the battery
is discharged. You may try jump start-
ing. See “(c) Jump starting” for further
instructions.
If the light is O.K., but the engine still will
not start, it needs adjustment or repair.
Call a Toyota dealer or qualified repair
shop.
NOTICE
Do not pull or pushstart the ve-
hicle. Your vehicle may suddenly
move when the engine starts, and
may damage itself or cause a colli-
sion. Also the threeway catalytic
converter may overheat and become a
fire hazard.
If the engine turns over at its normal
speed but will not start— 1. Turn the ignition key to “ACC” or “LOCK” and try starting the engine
again.
2. If the engine will not start, the engine may be flooded because of repeated
cranking. See “(b) Starting a flooded
engine” for further instructions.
3. If the engine still will not start, it needs adjustment or repair. Call a Toyota
dealer or qualified repair shop. If the engine will not start, your engine
may be flooded because of repeated
cranking.
If this happens, turn the key to “START”
with the accelerator pedal fully depressed.
Keep the key and accelerator pedal in
these positions for 15 seconds and re-
lease them. Then try starting the engine
with your foot off the accelerator pedal.
If the engine does not start after 15 se-
conds of cranking, release the key, wait
a few minutes and try again.
If the engine still will not start, it needs
adjustment or repair. Call a Toyota dealer
or qualified repair shop for assistance.
NOTICE
Do not crank for more than 30 se-
conds at a time. This may overheat
the starter and wiring systems.
If your vehicle will not start—
(a) Simple checks
(b) Starting a flooded engine
(5VZFE engine)

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If the engine will not start, your engine
may be flooded because of repeated
cranking.
If this happens, turn the ignition key to
“START” with the accelerator pedal held
down, and hold the key at this position for
about 30 seconds. Then the cranking hold
function stops cranking automatically, and
you can try starting the engine with your
foot off the accelerator pedal.
If the engine does not start, wait a few
minutes and try again.
If the engine still will not start, it needs
adjustment or repair. Call a Toyota dealer
or qualified repair shop for assistance. To avoid serious personal injury and
damage to your vehicle which might re-
sult from battery explosion, acid burns,
electrical burns, or damaged electronic
components, these instructions must be
followed precisely.
If you are unsure about how to follow this
procedure, we strongly recommend that
you seek the help of a competent me-
chanic or towing service.
CAUTION
Batteries contain sulfuric acid
which is poisonous and corrosive.
Wear protective safety glasses when
jump starting, and avoid spilling
acid on your skin, clothing, or ve-
hicle.
If you should accidentally get acid
on yourself or in your eyes, remove
any contaminated clothing and flush
the affected area with water imme-
diately. Then get immediate medical
attention. If possible, continue to
apply water with a sponge or cloth
while en route to the medical office.
The gas normally produced by a
battery will explode if a flame or
spark is brought near. Use only
standardized jumper cables and do
not smoke or light a match while
jump starting.
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.
NOTICE
The battery used for boosting must
be 12 V. Do not jump start unless you
are sure that the booster battery is
correct.
(b) Starting a flooded engine
(2UZFE engine)
(c) Jump starting