Possible causes and solutions:
1. Low transmission fluid level:
* Check the level and, if necessary, add the fluid recommended by the manufacturer.
2. Air in the system:
* Start the engine and shift the gear lever through all positions several times.
* This will help remove air from the system.
3. Faulty sensor:
* The input shaft speed sensor or the output shaft speed sensor may send incorrect data to the transmission control module (TCM), resulting in incorrect shifts.
* Test the sensors and replace them if necessary.
4. Worn clutch packs:
* Worn clutch packs can slip when shifting, causing shock.
* Clutch packs may need to be replaced.
5. Faulty solenoid:
* Hydraulic solenoids control the flow of fluid into the automatic transmission.
* Faulty solenoids can cause incorrect fluid pressure and jerky shifting.
* Identify and replace faulty solenoids.
6. Incorrect TCM settings:
* The TCM may be incorrectly programmed or adjusted after an automatic transmission repair.
*Make sure the TCM is programmed with the correct settings for your vehicle model and engine.
7. Mechanical problems:
* If the above reasons are excluded, the problem may be in the mechanical component of the automatic transmission, such as worn gears or bearings.
* Further diagnostics and possibly disassembly of the automatic transmission will be required.
Recommended actions:
* Contact the car service that repaired the automatic transmission to diagnose and fix the problem.
* Provide the mechanic with accurate information about the conditions under which the shaking occurs and any other symptoms.
* Follow the recommendations for automatic transmission care, including timely replacement of the fluid and filter.