Rock Auto and Amazon are 2 companies that sell this: # SE10002
They say they fit on a ton of cars including the 4Runner, model years 2003 - 2012.
NOTICE:
Replace the grommet even if it is not damaged when reusing the tire pressure warning valve and transmitter.
Check that there is no oil, water or lubricant around the rim hole, tire pressure warning valve and transmitter, washer and nut. Failing to do so may result in improper installation.
Check that there is no visible deformation, damage or other abnormalities on the tire pressure warning valve and transmitter.
Check that there is no foreign matter on the inner grommet and around the rim hole.
If the tire pressure warning valve and transmitter is installed upside down, it may be damaged or fail to transmit signals when running at high speeds.
If installing a new tire pressure warning valve and transmitter, write down the ID number before installation.
It is necessary to register the ID in the ECU after installation See: Tire Monitoring System\Testing and Inspection\Programming and Relearning.
TIRE AND WHEEL: TIRE PRESSURE WARNING SYSTEM: REGISTRATION
DESCRIPTION OF CODE REGISTRATION
It is necessary to register the transmitter ID in the tire pressure warning ECU when replacing the tire pressure warning valve and transmitter and/or tire pressure warning ECU.
Prepare all transmitter ID data before starting registration.
(a) Before registration
(1) In case of tire pressure warning ECU replacement:
Read the registered transmitter IDs that are stored in the old ECU using the Techstream and note them down.
If reading stored transmitter IDs is impossible due to malfunctions of components such as the tire pressure warning antenna and receiver, remove the tires from the wheels and check the IDs located on the tire pressure warning valves and transmitters See: Service Precautions.
(2) In case of tire pressure warning valve and transmitter replacement:
Take a note of the 7 digit number (transmitter ID) written on the tire pressure warning valve and transmitter.
NOTICE: The transmitter ID is written on the tire pressure warning valve and transmitter. It will be unable to be read after installing the tire pressure warning valve and transmitter on the tire and wheel. Therefore, take a note of the transmitter ID before installing the tire pressure warning valve and transmitter.
REGISTER TRANSMITTER ID
(a) Set the air pressure of all tires to the specified value See: Service Precautions.
(b) Turn the ignition switch OFF.
(c) Connect the Techstream to the DLC3.
(d) Turn the ignition switch ON and the Techstream on.
(e) Enter the following menus: Chassis / Tire Pressure Monitor / Utility / ID Registration /
(f) Perform the procedures displayed on the screen.
HINT:
The previously registered IDs will be deleted from the memory when the registration is completed.
If this step is not completed within 300 seconds, this mode will be canceled
(g) Confirmation of transmitter ID registration:
(1) Enter the following menus: Chassis / Tire Pressure Monitor / Data List /
(2) Read the "ID Tire Inflation Pressure" values.
(3) Confirm that the tire pressure data of all tires is displayed on the screen.
NOTICE:
It may take up to about 2 or 3 minutes to update the tire pressure data. If the values are not displayed after a few minutes, perform troubleshooting according to the inspection procedure for DTCs C2121/21 to C2125/25.
If the IDs have not been registered, DTC C2171/71 is set in the tire pressure warning ECU after 3 minutes or more.
If normal pressure values are displayed, the IDs have been registered correctly.
If the tire pressure values are not displayed after a few minutes, the IDs may be incorrect or the system may have a malfunction.
After all IDs are registered, DTC C2126/26 is set in the tire pressure warning ECU and the tire pressure warning light blinks for 1 minute and then comes on. When the tire pressure warning ECU successfully receives radio waves from all the transmitters whose IDs are stored in the ECU, DTC C2126/26 is deleted and the tire pressure warning light goes off.