Follow these instructions to keep the ATF cooler cleaner working properly:
Replace the two magnetic nonbypass spin-on filters after every 20 hours of use, based on the hour meter, or when you notice a restriction in the ATF flow.
Check the level and condition of the fluid in the tank before each use.
Replace the ATF in the tank when it looks dark or dirty.

Transmission End Cover Selector Control Shaft Oil Seal Replacement (A/T)
Special Tools Required
Driver Handle, 15 x 135L 07749-0010000
Bearing Driver Attachment, 22 x 24 mm 07746-0010800
Remove the oil seal from the end cover.
Install the new oil ...
Radiator Connecting Pipe Replacement
Drain the engine coolant.
Remove the thermostat housing.
Remove the connecting pipe (A).
Install the connecting pipe with a new O-ring (B).
...
A/T Housing Idler Gear Shaft Removal and Installation (A/T)
Remove the snap ring (A), the cotter retainer (B), and the cotters (C)
from the idler gear shaft (D), then remove the idler gear shaft. Do not
distort the snap ring.
Check ...