You have a 2000 Daewoo Lanos with auto trans shifting problem after warming up to operating temp frequently changed filter and oil no metal in think is any ideas?

1. Solenoids: Faulty solenoids in the transmission can cause shifting issues, especially when the transmission is warm.




2. Transmission Control Module (TCM): The TCM is responsible for controlling the shifting of gears in an automatic transmission. If the TCM is malfunctioning, it can cause shifting problems.




3. Hydraulic Pressure: Insufficient hydraulic pressure in the transmission can lead to shifting issues. This can be due to a low transmission fluid level, a faulty pump, or a clogged filter.




4. Torque Converter: A faulty torque converter can also cause shifting problems, particularly when the transmission is warm.




5. Mechanical Issues: Worn or damaged internal transmission components, such as gears, synchronizers, or shift forks, can also cause shifting problems.

Troubleshooting:

- Check the transmission fluid level and condition. If the fluid is low or dirty, add or change the fluid as needed.

- Inspect the transmission filter. If the filter is clogged or dirty, replace it.

- Check for any leaks in the transmission. If there are any leaks, have them repaired.

- Scan the vehicle for any trouble codes that may be related to the transmission.

- If no trouble codes are found, have a qualified technician inspect the transmission.