how to fix my BMW 5 Series G30/G31 (2017-2024) transmission slipping when shifting

Solution

1. Preparation

• Tools Required: OBD-II scanner, transmission fluid pressure gauge, socket set, torque wrench, funnel, and clean rags.
• Ensure the vehicle is parked on a level surface, and the engine is cool.
• Disconnect the battery to prevent electrical issues while working on the transmission.

2. Check and Replace Transmission Fluid

• Sub-steps:
  1. Locate the transmission dipstick or fill plug.
  2. Remove the dipstick or fill plug and check the fluid level; it should be within the specified range.
  3. If the fluid level is low, add the recommended transmission fluid (BMW ATF).
  4. If the fluid is dark or has a burnt smell, proceed to drain and replace the fluid.
  5. To drain, locate the transmission pan, remove the bolts, and allow the old fluid to drain into a suitable container.
  6. Replace the transmission filter if applicable.
  7. Reinstall the pan using a new gasket or sealant, and torque the bolts to manufacturer's specifications.
  8. Refill the transmission with the correct amount of new fluid through the dipstick or fill plug.

3. Inspect and Replace Transmission Components (if necessary)

• Sub-steps:
  1. If slipping persists, inspect the transmission for worn components such as clutch packs or bands.
  2. Remove the transmission from the vehicle if major repairs are needed.
  3. Replace any damaged or worn components according to manufacturer specifications.
  4. Reinstall the transmission and ensure all connections are secure.

4. Reprogram the Transmission Control Module (if applicable)

• Sub-steps:
  1. Reconnect the battery.
  2. Use the OBD-II scanner to check for any TCM updates.
  3. Follow the scanner instructions to update or reprogram the TCM.
  4. Clear any error codes and perform a test drive.