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.
Shifter Input and Linkage
Paddle Shifter (Downshift Switch) Replacement (A/T)
SRS components are located in this area. Review the SRS component locations
and the precautions and procedures before doi ...
Throttle Body Removal/Installation
caution
Do not insert your fingers into the installed throttle body when you
turn the ignition switch to ON (II) or while the ignition switch is in
ON (II). If you d ...
Flywheel Inspection
Remove the ring gear holder.
Inspect the ring gear teeth for wear and damage.
Inspect the clutch disc mating surface on the flywheel for wear, cracks,
and burning.
...