The sealing rings are synthetic resin with chamfered ends. Check the condition of the sealing rings, and replace them only if they are worn, distorted, or damaged.
For a better fit, squeeze sealing rings together slightly before installing them.

Apply ATF to the new sealing rings, then install them on the secondary shaft.

After installing the sealing rings, verify the following:
The rings are fully seated in the groove.
The rings are not twisted.
The chamfered ends of the rings are properly joined.
Automatic Transmission
Release the parking brake.
Start the engine.
Shift to D, then to N.
Turn off the engine.
Leave the ignition switch in ACCESSORY (I) so the steering wheel does not
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Chassis
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Transmission Fluid
Automatic Transmission Fluid
Specified fluid: Honda ATF DW-1 (automatic transmission fluid)
Check the fluid level when the engine is at normal operating temperature.
1. Park on level ground, and ...