Transmission not shifting properly

Good evening

This sounds like a valve body issue. If 1 and 2 work manually, then it sounds like the valve body not allowing fluid flow to the forward clutch pack.

https://www.2carpros.com/articles/automatic-transmission-problems

Are there any codes set in the system?

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Roy

1. Raise and suitably support the vehicle.
2. Remove the transmission oil pan and filter.
3. Disconnect the electrical connectors from the control valve body components.
4. Remove the torque converter clutch (TCC) solenoid bolts.
5. Remove the wiring harness bolts.


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6. Remove the TCC solenoid assembly with the O-ring seal and the wiring harness, then reposition.


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7. Remove the transmission pressure switch assembly bolts.
8. Remove the pressure switch assembly.


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9. Remove the manual detent spring bolt.
10. Remove the manual detent spring.


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11. Remove the remaining control valve body bolts.
12. Disconnect the manual valve link and remove the control valve body from the transmission case.
13. Inspect the control valve body. Refer to Transmission Unit Repair for cleaning, inspection, and repair procedures of the control valve body.