how to fix jerking when shifting in my BMW 3 Series E90/E91 (2005-2012) transmission

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface with the engine off and cooled down.
• Disconnect the battery to prevent electrical shorts.

2. Check Transmission Fluid

• Tools Required: Transmission dipstick (if applicable), funnel, drain pan.
• Remove the transmission dipstick and check fluid level.
• If low, add the appropriate ATF (Automatic Transmission Fluid) as specified in the owner’s manual.
• If dirty or burnt, plan to replace the fluid.

3. Replace Transmission Fluid and Filter

• Tools Required: Socket set, torque wrench, fluid pump, funnel, drain pan.
• Remove the transmission pan bolts using a socket wrench and carefully lower the pan to drain fluid.
• Remove the old filter from the transmission and install the new filter.
• Clean the transmission pan and replace the gasket.
• Reinstall the transmission pan and torque the bolts to manufacturer specifications (typically 8-10 Nm).
• Fill the transmission with new ATF using a funnel.

4. Update Transmission Control Module (if necessary)

• Tools Required: OBD-II scanner or BMW diagnostic tool.
• Connect the scanner to the OBD-II port and check for software updates for the TCM.
• Follow the scanner prompts to perform any necessary updates.

5. Test Drive and Adjust

• Reconnect the battery and start the engine.
• Allow the transmission to warm up by letting the vehicle idle for a few minutes.
• Take the vehicle for a test drive to ensure proper shifting and absence of jerking.