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.

Valve Body and ATF Strainer Removal (A/T)
Remove the ATF feed pipe (A) from the regulator valve body (B).
Remove the ATF feed pipes (C) (D) from the servo body (E).
Remove the ATF strainer (F) (two bolts).
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Rocker Arm Assembly Removal
Remove the cylinder head cover.
Loosen the rocker arm adjusting screws (A).
Unscrew the rocker shaft mounting bolts two turns at a time in the
sequence shown.
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Intermediate Shaft Removal (A/T)
Drain the transmission fluid. Reinstall the drain plug with a new sealing
washer.
Remove the right driveshaft.
Remove the shift cable cover (A).
Re ...