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.
Output Shaft (Countershaft) Speed Sensor Replacement (M/T)
M/T
Raise the vehicle on a lift.
Disconnect the output shaft (countershaft) speed sensor connector (A).
Remove the output shaft (countershaft) speed sensor (B).
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Gauges
TripMeter
This meter shows the number of miles (U.S.) or kilometers (Canada) driven since
you last reset it.
There are two trip meters: Trip A and Trip B. Switch between these displays by
pres ...
Transmission Housing and Shaft Assembly Removal (A/T)
Special Tools Required
Housing Puller 07HAC-PK40102
Remove the dipstick (A).
Remove the shift solenoid valve cover (B), the dowel pins (C), and the
gasket (D).
Di ...