2023 TOYOTA TUNDRA HYBRID maintenance

4576-3. Do-it-yourself maintenance
Owners Manual_USA_M0C052_en
6
Maintenance and care
Fuse boxes ( P.486)
Power control unit coolant reservoir ( P.460)
Intercooler coolant reservoir ( P.460)
Engine coolant reservoir ( P.460)
Engine oil filler cap ( P.458)
Engine oil level dipstick ( P.458)
Brake fluid reservoir ( P.461)
Engine radiator ( P.461)
Condenser ( P.461)
Electric cooling fans
Radiator cooling fan ( P.460)
Washer fluid tank ( P.462)
Intercooler radiators ( P.460)
Engine compar tment
Components

4586-3. Do-it-yourself maintenance
Owners Manual_USA_M0C052_en
With the engine at operating
temperature and turned off,
check the oil level on the dip-
stick.
■Checking the engine oil
1 Park the vehicle on level
ground. After warming up the
engine and turning off the
engine, wait more than 5
minutes for the oil to drain
back into the bottom of the
engine.
2 Holding a rag under the end,
pull the dipstick out.
3 Wipe the dipstick clean.
4 Reinsert the dipstick fully with
its protruding areas ( in the illustration) pointing towards
engine.
5 Holding a rag under the end,
pull the dipstick out and
check the oil level.
Low
Normal
Excessive
6 Wipe the dipstick and reinsert
it fully.
■Checking the oil type and
preparing the items needed
Make sure to check the oil type
and prepare the items needed
before adding oil.
 Engine oil selection
P.543
 Oil quantity (Low  Full)
1.6 qt. (1.5 L, 1.3 Imp.qt.)
Checking and adding the
engine oil

4596-3. Do-it-yourself maintenance
Owners Manual_USA_M0C052_en
6
Maintenance and care
 Items
Clean funnel
■Adding engine oil
If the oil level is below or near
the low level mark, add engine
oil of the same type as that
already in the engine.
1 Remove the oil filler cap by
turning it counterclockwise.
2 Add engine oil slowly, check-
ing the dipstick.
3 Install the oil filler cap by
turning it clockwise.
■Engine oil consumption
A certain amount of engine oil will
be consumed while driving. In the
following situatio ns, oil consump-
tion may increase, and engine oil
may need to be ref illed in between
oil maintenance intervals.
●When the engine is new, for
example directly after purchasing
the vehicle or after replacing the
engine
●If low quality oil or oil of an inap-
propriate viscosity is used
●When driving at high engine
speeds or with a heavy load,
when towing, or when driving
while accelerating o r decelerating
frequently
●When leaving the engine idling for a long time, or when driving fre-
quently through heavy traffic
■After changing the engine oil
The engine oil maintenance data
should be reset. Pe rform the follow-
ing procedures:
1 Press or of the meter
control switches and select .
2 Press or of the meter
control switches, select the
“Vehicle Settings” and then press
.
3 Press or of the meter
control switches, select the “Oil
Maintenance” and then press
.
4 Select the “Yes” and push .
“Reset Complete” is displayed
on the multi-info rmation display.
WARNING
■Used engine oil
●Used engine oil contains poten-
tially harmful contaminants
which may cause skin disorders
such as inflammation and skin
cancer, so care should be taken
to avoid prolonged and
repeated contact. To remove
used engine oil from your skin,
wash thoroughly with soap and
water.
●Dispose of used oil and filters
only in a safe and acceptable
manner. Do not dispose of used
oil and filters in h ousehold trash,
in sewers or onto the ground.
Call your Toyota dealer, service
station or auto parts store for
information concerning recy-
cling or disposal.
●Do not leave used engine oil
within the reach of children.

4606-3. Do-it-yourself maintenance
Owners Manual_USA_M0C052_en
The coolant level is satisfactory
if it is between the “F” and “L”
lines on the reservoir when the
hybrid system is cold.
Engine coolant Engine coolant reservoir cap
“F” line
“L” line
If the level is on or below the “L”
line, add coolant up
to the “F” line.
(  P.535)
Intercooler coolant
Intercooler coolant reservoir
cap
“F” line
“L” line
If the level is on or below the “L”
line, add coolant up to the “F” line.
(  P.535)
Power control unit coolant
Power control unit coolant
reservoir cap
“FULL” line
NOTICE
■To prevent serious engine
damage
Check the oil level on a regular
basis.
■When replacing the engine oil
●Be careful not to spill engine oil
on the vehicle components.
●Avoid overfilling, or the engine
could be damaged.
●Check the oil le vel on the dip-
stick every time you refill the
vehicle.
●Be sure the engine oil filler cap
is properly tightened.
■If oil is spilled on the engine
cover
To prevent the engine cover from
being damaged, remove any
engine oil from the engine cover
as soon as possible using a neu-
tral detergent. Do not use an
organic solvent such as brake
cleaner.
Checking the coolant

4616-3. Do-it-yourself maintenance
Owners Manual_USA_M0C052_en
6
Maintenance and care
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( P.535)
■Coolant selection
Only use “Toyota Super Long Life
Coolant” or a similar high quality
ethylene glycol based non-silicate,
non-amine, non-nitrite, and non-
borate coolant with long-life hybrid
organic acid technology.
U.S.A.:“Toyota Super Long Life
Coolant” is a mixture of 50% coolant
and 50% deionized water.
(Minimum temperature: -31°F [-
35°C])
Canada: “Toyota Super Long Life
Coolant” is a mixture of 55% coolant
and 45% deionized water.
(Minimum temperature: -44°F [-
42°C])
For more details about coolant, con-
tact your Toyota dealer.
■If the coolant level drops within
a short time of replenishing
Visually check the radiator, hoses,
engine coolant reser voir cap, inter-
coolant reservoir cap, drain cock
and water pump.
If you cannot find a leak, have your
Toyota dealer test the cap and
check for leaks in the cooling sys-
tem.
Check the radiator, condenser
and intercooler radiators and
clear away any foreign objects.
If either of the above parts is
extremely dirty or you are not
sure of their condition, have
your vehicle inspected by your
Toyota dealer.
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
WARNING
■When the hybrid system is
hot
Do not remove the coolant reser-
voir cap.
The cooling system may be under
pressure and may spray hot cool-
ant if the cap is removed, causing
serious injuries, such as burns.
NOTICE
■When adding coolant
Coolant is neither plain water nor
straight antifreeze. The correct
mixture of water and antifreeze
must be used to provide proper
lubrication, corrosion protection
and cooling. Be sure to read the
antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to
prevent it from damaging parts or
paint.
Checking the radiator,
condenser and inter-
cooler radiators
WARNING
■When the hybrid system is
hot
Do not touch the radiator, con-
denser or intercooler radiators or
condenser as they may be hot
and cause serious injuries, such
as burns.
Checking and adding the
brake fluid

4626-3. Do-it-yourself maintenance
Owners Manual_USA_M0C052_en
lines on the tank.
Brake fluid reservoir cap
“MAX” line
“MIN” line
■Adding fluid
Make sure to check the fluid
type and prepare the necessary
item.
 Fluid type
FMVSS No.116 DOT 3 or SAE
J1703 brake fluid
FMVSS No.116 DOT 4 or SAE
J1704 brake fluid
Item
Clean funnel
■Brake fluid can absorb moisture
from the air
Excess moisture in the brake fluid
can cause a dangerous loss of brak-
ing efficiency. Use only newly
opened brake fluid.
If any washer does not work the
washer tank may be empty. Add
washer fluid.
WARNING
■When filling the reservoir
Take care as brake fluid can harm
your hands and eyes and damage
painted surfaces.
If fluid gets on your hands or in
your eyes, flush the affected area
with clean water immediately.
If you still experi ence discomfort,
see a doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level
to go down slight ly as the brake
pads wear out or when the fluid
level in the accumulator is high.
If the reservoir needs frequent
refilling, there m ay be a serious
problem.
Adding the washer fluid
WARNING
■When adding washer fluid
Do not add washer fluid when the
hybrid system is hot or operating
as washer fluid contains alcohol
and may catch fire if spilled on the
hybrid system, etc.

4636-3. Do-it-yourself maintenance
Owners Manual_USA_M0C052_en
6
Maintenance and care
The 12-volt battery is located in
the left-hand side of the rear
seat under.
1 Raising the bottom cushion.
( P.135)
2 Remove the battery cover.
Use the flat-head screwdriver or
mechanical key ( P.110).
■Before recharging
When recharging, the 12-volt bat-
tery produces hydrogen gas which
is flammable and explosive. There-
fore, observe the following precau-
tions before recharging:
●If recharging with the 12-volt bat-
NOTICE
■Do not use any fluid other
than washer fluid
Do not use soapy water or anti-
freeze instead of washer fluid.
Doing so may cause streaking on
the vehicle’s painted surfaces, as
well as damaging the pump lead-
ing to problems of the washer
fluid not spraying.
■Diluting washer fluid
Dilute washer fluid with water as
necessary.
Refer to the freezing tempera-
tures listed on the label of the
washer fluid bottle.
12-volt batter y
Location
Removing the 12-volt bat-
tery cover

4646-3. Do-it-yourself maintenance
Owners Manual_USA_M0C052_entery installed on the vehicle, be
sure to disconnect the ground
cable.
●Make sure the power switch on
charger is off when connecting
and disconnecting the charger
cables to the 12-volt battery.
■After recharging/reconnecting
the 12-volt battery
●Unlocking the doors using the
smart key system may not be pos-
sible immediately after reconnect-
ing the 12-volt battery. If this
happens, use the wireless remote
control or the mechanical key to
lock/unlock the doors.
●Start the hybrid system with the
power switch in ACC. The hybrid
system may not start with the
power switch turned off. However,
the hybrid system will operate nor-
mally from the second attempt.
●The power switch mode is
recorded by the vehicle. If the 12-
volt battery is
reconnected, the
vehicle will return the power
switch mode to the status it was in
before the 12-volt battery was dis-
connected. Make sure to turn off
the power switch before discon-
necting the 12-volt battery. Take
extra care when connecting the
12-volt battery if the power switch
mode prior to discharge is
unknown.
●When the 12-volt b attery is recon-
nected, start the hybrid system,
depress the brake pedal, and con-
firm that it is possible to shift into
each shift position.
If the system will not start even after
multiple attempts, contact your Toy-
ota dealer.
WARNING
■Chemicals in the 12-volt bat-
tery
The 12-volt battery contains poi-
sonous and corrosive sulfuric acid
and may produce hydrogen gas
which is flammable and explosive.
To reduce the risk of death or seri-
ous injury, take the following pre-
cautions while working on or near
the 12-volt battery:
●Do not cause sparks by touch-
ing the 12-volt battery terminals
with tools.
●Do not smoke or light a match
near the 12-volt battery.
●Avoid contact with eyes, skin
and clothes.
●Never inhale or swallow electro-
lyte.
●Wear protective safety glasses
when working near the 12-volt
battery.
●Keep children away from the
12-volt battery.
■Where to safely charge the
12-volt battery
Always charge the 12-volt battery
in an open area. Do not charge
the 12-volt battery in a garage or
closed room where there is insuf-
ficient ventilation.
■Emergency measures regard-
ing electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean
water for at least 15 minutes
and get immediate medical
attention. If possible, continue
to apply water with a sponge or
cloth while traveling to the near-
est medical facility.