2008 TOYOTA TUNDRA coolant temperature

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2008 TUNDRA from Apr. ’08 Prod. (OM 34477U)
(b) Normal driving
1. Start the engine as instructed in “How to start the engine” on page 474 in
Section 3. The transmission must be in
“P” or “N”.
When the front drive control switch knob
is in “4L” (low −speed position, four −wheel
drive), the driving pattern selector setting
has no effect on gear shift timing. (See
“Four −wheel drive system” on page 240 in
this Section for information of the front
drive control lever.)
2. With your foot holding down the brake pedal, shift the selector lever to “D”.
When the lever is in the “D” position, the
automatic transmission system will select
the most suitable gear for running condi-
tions such as normal cruising, hill climb-
ing, hard towing, etc.
Always use the “D” position for better fuel
economy and quieter driving. If the engine
coolant temperature is low or when the
front drive control switch knob is in “4L”
(low −speed position, four −wheel drive), the
transmission will not shift into the over-
drive gear even in the “D” position. (See
“Four −wheel drive system” on page 240 in
this Section for information of the front
drive control.)CAUTION
Never put your foot on the accelera-
tor pedal while shifting.
3. Release the parking brake and brake pedal. Depress the accelerator pedal
slowly for smooth starting.
AI (Artificial Intelligence) shifting con-
trol—
AI shifting control selects the most
suitable shift range automatically ac-
cording to the driver’s operation and
driving condition.
AI shifting control operates automatical-
ly with the selector lever in the “D”
position. When the lever is moved to
the “S” position, this function will be
cancelled.
Shifting control on the slope:
On inclines, you can drive smoothly
with reduced shifting quantity. On de-
clines, the vehicle will shift down auto-
matically to obtain optimum engine
braking and reduce the driver ’s foot
braking load.
Automatic shifting point change con-
trol:
The most suitable shift range is se-
lected depending on the driver ’s accel-
erator pedal operation and vehicle con-
dition.
(c) Driving in “S” mode
The shift range position can be
changed in “S” mode. When the selec-
tor lever is in the “S” position, the
shift range position can be switched
between “5” (fifth range) and “1” (first
range) by shifting the selector lever to
the “+” (up) or “” (down) position. By
shifting the lever to the “+” (up) posi-
tion and holding it for at least 1 sec-
ond, the highest shift range position
can be obtained. However, it cannot be
changed while cruise control is acti-
vated. When the selector lever is
shifted to the “S” position, shift range
position “4” (fourth range) is selected
automatically.
However, if the selector lever is shifted
to the “S” position when AI shifting
control is being performed, the initial
shift range position may be “3” (third
range). This is because the suitable
shift range is selected depending on
the driving condition.

219
2008 TUNDRA from Apr. ’08 Prod. (OM 34477U)
(b) Normal driving
1. Start the engine as instructed in “How to start the engine” on page 474 in
Section 3. The transmission must be in
“P” or “N”.
When the front drive control switch knob
is in “4L” (low −speed position, four −wheel
drive), the driving pattern selector setting
has no effect on gear shift timing. (See
“Four −wheel drive system” on page 240 in
this Section for information of the front
drive control lever.)
2. With your foot holding down the brake pedal, shift the selector lever to “D”.
When the lever is in the “D” position, the
automatic transmission system will select
the most suitable gear for running condi-
tions such as normal cruising, hill climb-
ing, hard towing, etc.
Always use the “D” position for better fuel
economy and quieter driving. If the engine
coolant temperature is low or when the
front drive control switch knob is in “4L”
(low −speed position, four −wheel drive), the
transmission will not shift into the over-
drive gear even in the “D” position. (See
“Four −wheel drive system” on page 240 in
this Section for information of the front
drive control.)CAUTION
Never put your foot on the accelera-
tor pedal while shifting.
3. Release the parking brake and brake pedal. Depress the accelerator pedal
slowly for smooth starting.
AI (Artificial Intelligence) shifting con-
trol—
AI shifting control selects the most
suitable shift range automatically ac-
cording to the driver’s operation and
driving condition.
AI shifting control operates automatical-
ly with the selector lever in the “D”
position. When the lever is moved to
the “S” position, this function will be
cancelled.
Shifting control on the slope:
On inclines, you can drive smoothly
with reduced shifting quantity. On de-
clines, the vehicle will shift down auto-
matically to obtain optimum engine
braking and reduce the driver ’s foot
braking load.
Automatic shifting point change con-
trol:
The most suitable shift range is se-
lected depending on the driver ’s accel-
erator pedal operation and vehicle con-
dition.
(c) Driving in “S” mode
The shift range position can be
changed in “S” mode. When the selec-
tor lever is in the “S” position, the
shift range position can be switched
between “6” (sixth range) and “1” (first
range) by shifting the selector lever to
the “+” (up) or “” (down) position. By
shifting the lever to the “+” (up) posi-
tion and holding it for at least 1 sec-
ond, the highest shift range position
can be obtained. However, it cannot be
changed while cruise control is acti-
vated. When the selector lever is
shifted to the “S” position, shift range
position “4” (fourth range) or “5” (fifth
range) is selected depending on the ve-
hicle speed.

227
2008 TUNDRA from Apr. ’08 Prod. (OM 34477U)
(b) Normal driving
1. Start the engine as instructed in “How to start the engine” on page 474 in
Section 3. The transmission must be in
“P” or “N”.
When the front drive control switch knob
is in “4L” (low −speed position, four −wheel
drive), the driving pattern selector setting
has no effect on gear shift timing. (See
“Four −wheel drive system” on page 240 in
this Section for information of the front
drive control lever.)
2. With your foot holding down the brake pedal, shift the selector lever to “D”.
When the lever is in the “D” position, the
automatic transmission system will select
the most suitable gear for running condi-
tions such as normal cruising, hill climb-
ing, hard towing, etc.
Always use the “D” position for better fuel
economy and quieter driving. If the engine
coolant temperature is low or when the
front drive control switch knob is in “4L”
(low −speed position, four −wheel drive), the
transmission will not shift into the over-
drive gear even in the “D” position. (See
“Four −wheel drive system” on page 240 in
this Section for information of the front
drive control.)CAUTION
Never put your foot on the accelera-
tor pedal while shifting.
3. Release the parking brake and brake pedal. Depress the accelerator pedal
slowly for smooth starting.
AI (Artificial Intelligence) shifting con-
trol—
AI shifting control selects the most
suitable shift range automatically ac-
cording to the driver’s operation and
driving condition.
AI shifting control operates automatical-
ly with the selector lever in the “D”
position. When the lever is moved to
the “S” position, this function will be
cancelled.
Shifting control on the slope:
On inclines, you can drive smoothly
with reduced shifting quantity. On de-
clines, the vehicle will shift down auto-
matically to obtain optimum engine
braking and reduce the driver ’s foot
braking load.
Automatic shifting point change con-
trol:
The most suitable shift range is se-
lected depending on the driver ’s accel-
erator pedal operation and vehicle con-
dition.
(c) Driving in “S” mode
The shift range position can be
changed in “S” mode. When the selec-
tor lever is in the “S” position, the
shift range position can be switched
between “5” (fifth range) and “1” (first
range) by turning the “S” mode switch
of the selector lever to the “+” (up) or
“” (down) direction. By turning the
“S” mode switch to the “+” (up) direc-
tion and holding it for at least 1 sec-
ond, the highest shift range position
can be obtained. However, it cannot be
changed while cruise control is acti-
vated. When the selector lever is
shifted to the “S” position, shift range
position “4” (fourth range) is selected
automatically.
However, if the selector lever is shifted
to the “S” position when AI shifting
control is being performed, the initial
shift range position may be “3” (third
range). This is because the suitable
shift range is selected depending on
the driving condition.

234
2008 TUNDRA from Apr. ’08 Prod. (OM 34477U)
(b) Normal driving
1. Start the engine as instructed in “How to start the engine” on page 474 in
Section 3. The transmission must be in
“P” or “N”.
When the front drive control switch knob
is in “4L” (low −speed position, four −wheel
drive), the driving pattern selector setting
has no effect on gear shift timing. (See
“Four −wheel drive system” on page 240 in
this Section for information of the front
drive control lever.)
2. With your foot holding down the brake pedal, shift the selector lever to “D”.
When the lever is in the “D” position, the
automatic transmission system will select
the most suitable gear for running condi-
tions such as normal cruising, hill climb-
ing, hard towing, etc.
Always use the “D” position for better fuel
economy and quieter driving. If the engine
coolant temperature is low or when the
front drive control switch knob is in “4L”
(low −speed position, four −wheel drive), the
transmission will not shift into the over-
drive gear even in the “D” position. (See
“Four −wheel drive system” on page 240 in
this Section for information of the front
drive control.)CAUTION
Never put your foot on the accelera-
tor pedal while shifting.
3. Release the parking brake and brake pedal. Depress the accelerator pedal
slowly for smooth starting.
AI (Artificial Intelligence) shifting con-
trol—
AI shifting control selects the most
suitable shift range automatically ac-
cording to the driver’s operation and
driving condition.
AI shifting control operates automatical-
ly with the selector lever in the “D”
position. When the lever is moved to
the “S” position, this function will be
cancelled.
Shifting control on the slope:
On inclines, you can drive smoothly
with reduced shifting quantity. On de-
clines, the vehicle will shift down auto-
matically to obtain optimum engine
braking and reduce the driver ’s foot
braking load.
Automatic shifting point change con-
trol:
The most suitable shift range is se-
lected depending on the driver ’s accel-
erator pedal operation and vehicle con-
dition.
(c) Driving in “S” mode
The shift range position can be
changed in “S” mode. When the selec-
tor lever is in the “S” position, the
shift range position can be switched
between “6” (sixth range) and “1” (first
range) by turning the “S” mode switch
of the selector lever to the “+” (up) or
“” (down) direction. By turning the
“S” mode switch to the “+” (up) direc-
tion and holding it for at least 1 sec-
ond, the highest shift range position
can be obtained. However, it cannot be
changed while cruise control is acti-
vated. When the selector lever is
shifted to the “S” position, shift range
position “4” (fourth range) or “5” (fifth
range) is selected depending on the ve-
hicle speed.

242
2008 TUNDRA from Apr. ’08 Prod. (OM 34477U)
CAUTION
Never operate the front drive control
switch knob if the wheels are slip-
ping. Stop the slipping or spinning
before operating.
To shift from “4H” to “2WD”, reduce the
vehicle speed to less than 100 km/h (62
mph) and turn the front drive control
switch knob fully counterclockwise.
When you operate the front drive control
switch knob from “4H” to “2WD” with the
vehicle speed at 100 km/h (62 mph) or
higher, the “4HI” indicator light continues
to blink and buzzer sounds. When the
switch knob is returned from “2WD” to
“4H”, the indicator light turns off and the
buzzer stops sounding.
If the “4HI” (high speed four −wheel drive)
indicator light continues to blink when you
operate the front drive control switch knob
from the “4H” to the “2WD” position, this
reminds you that the transfer mode is not
securely in “2WD” mode. Drive straight
ahead while accelerating or decelerating,
or drive forward or backward for a short
distance. If there is any malfunction within the
brake system, “4HI” or “4LO” indicator
light blinks and the transfer mode may not
be able to be shifted from “4H” to “2WD”.
If the indicator light continues to blink
even if doing so, contact your Toyota
dealer as soon as possible. There may be
a trouble in the four
−wheel drive system.
CAUTION
Never operate the front drive control
switch knob if the wheels are slip-
ping. Stop the slipping or spinning
before operating.
SHIFTING BETWEEN “4H” AND “4L”
To shift between “4H” and “4L”
1. Bring the vehicle to a complete stop with the brake pedal held down.
2. Shift the automatic transmission selec- tor lever into “N”.
3. To shift from “4H” to “4L”, push and turn the front drive control switch knob
fully clockwise.
To shift from “4L” to “4H”, turn the
front drive control switch knob counter-
clockwise. 4. Maintain this condition until the “4LO”
or “4HI” indicator light comes on.
If the “4LO” indicator light continues to
blink...
If this indicator light continues to blink
when you operate the front drive control
switch knob to the “4H” or “4L” position,
stop the vehicle completely, shift the auto-
matic transmission selector lever securely
into “N” and operate the switch knob
again.
INFORMATION
 If the engine coolant temperature is
too low the transfer mode may not
be able to be shifted. When the en-
gine is warmer operate the switch
knob again.
 If the automatic transmission selec-
tor lever is moved before the indi-
cator comes on, the transfer mode
may not be shifted completely. In
this case, stop the vehicle com-
pletely, return the automatic trans-
mission selector lever to “N” and
operate the switch knob again.

494
2008 TUNDRA from Apr. ’08 Prod. (OM 34477U)
In order to maintain engine braking effi-
ciency when driving on a long steep
downgrade, do not use the transmis-
sion in “D”. Select an appropriate shift
range in “S” mode (See “Automatic
transmission” on page 211 in Section
1−7).
Because of the added load of the trail-
er, your vehicle’s engine may overheat
on hot days (at temperatures over
30 C [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” on page 502 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”. Avoid park-
ing 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 “P” and turn off the engine.
When restarting out after parking on a
slope: 1. With the transmission in “P” position, start the engine. Be sure to keep the
brake pedal depressed.
2. Shift into gear.
3. Release the parking brake and brake pedal, 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 use cruise control when you
are towing down long, steep grades
or with heavy loads.
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.

502
2008 TUNDRA from Apr. ’08 Prod. (OM 34477U)
If your engine stalls while driving...
1. Reduce your speed gradually, keeping a straight line. Move cautiously off the
road to a safe place.
2. Turn on your emergency flashers.
3. Turn the engine switch to the “ACC” or “LOCK” position, and try starting the
engine again.
If the engine will not start, see “If your
vehicle will not start” on page 498 in this
Section.
CAUTION
If the engine is not running, the pow-
er assist for the brakes and steering
will not work so steering and braking
will be much harder than usual.
If engine speed does not increase when
the accelerator pedal is depressed, there
may be a problem somewhere in the elec-
tronic throttle control system.
At this time, vibration may occur. Howev-
er, if you depress the accelerator pedal
more firmly and slowly, you can drive your
vehicle at low speeds. Have your vehicle
checked by your Toyota dealer as soon as
possible.
Even if the abnormality of the electronic
throttle control system is corrected during
low speed driving, the system may not be
recovered until the engine is stopped and
the engine switch is turned to the “ACC”
or “LOCK” position.
CAUTION
Be especially careful to prevent erro-
neous pedal operation.
If your engine coolant temperature
gauge indicates overheating, if you ex-
perience a loss of power, or if you hear
a loud knocking or pinging noise, the
engine has probably overheated. You
should follow this procedure... 1. Pull safely off the road, stop the ve- hicle and turn on your emergency
flashers. Put the transmission in “P”
and apply the parking brake. Turn off
the air conditioning if it is being used.
2. If coolant or steam is boiling out of the radiator or reservoir, stop the engine.
Wait until the steam subsides before
opening the hood. If there is no coolant
boiling over or steam, leave the engine
running.
CAUTION
To help avoid personal injury, keep
the hood closed until there is no
steam. Escaping steam or coolant is
a sign of very high pressure.
If your engine stalls while
driving If you cannot incr
ease engine
speed If your vehicle overheats

503
2008 TUNDRA from Apr. ’08 Prod. (OM 34477U)
3. Visually check to see if the engine
drive belt (fan belt) is broken or loose.
Look for obvious coolant leaks from the
radiator, hoses, and under the vehicle.
However, note that water draining from
the air conditioning is normal if it has
been used.
CAUTION
When the engine is running, keep
hands and clothing away from the
moving fan and engine drive belts.
4. If the engine drive belt is broken or thecoolant is leaking, stop the engine im-
mediately. Call a Toyota dealer for as-
sistance.
5. If the engine drive belt is O.K. and there are no obvious leaks, you may
help the engine cool down more quickly
by running it at about 1500 rpm for a
few minutes with the accelerator pedal
lightly depressed.
6. Check the coolant reservoir. If it is dry, add coolant to the reservoir while the
engine is running. Fill it about half full.
For the coolant type, See “Coolant type
selection” on page 551 in Section 7 −2.
CAUTION
Do not attempt to remove the radiator
cap when the engine and radiator are
hot. Serious injury could result from
scalding hot fluid and steam blown
out under pressure.
7. After the engine coolant temperature
has cooled to normal, again check the
coolant level in the reservoir. If neces-
sary, bring it up to half full again. Seri-
ous coolant loss indicates a leak in the
system. You should have it checked as
soon as possible at your Toyota dealer.
1. Reduce your speed gradually, keeping a straight line. Move cau-
tiously off the road to a safe place
well away from the traffic. Avoid
stopping on the center divider of
a highway. Park on a level spot
with firm ground.
2. Stop the engine and turn on your emergency flashers.
3. With the transmission in “P” firmly set the parking brake.
4. Have everyone get out of the ve- hicle on the side away from traffic.
5. Read the following instructions thoroughly.
If you have a flat tire—