why is my BMW 5 Series leaking transmission fluid

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent any electrical issues.
• Ensure the vehicle is on a level surface and securely lifted using jack stands.

2. Drain the Transmission Fluid

• Place a drain pan underneath the transmission pan.
• Remove the transmission pan bolts using a socket set.
• Carefully lower the pan to allow the fluid to drain completely into the drain pan.

3. Replace Seals and Gaskets

• Remove the old gasket and inspect the sealing surfaces for any damage.
• Clean the gasket surfaces on both the transmission and the pan using a scraper.
• Install a new gasket and replace any worn transmission seals.

4. Reinstall the Transmission Pan

• Position the transmission pan back onto the transmission.
• Hand-tighten the bolts before using a torque wrench to tighten to manufacturer specifications (typically around 10-15 Nm).
• Refill the transmission with the recommended fluid type (typically BMW ATF or compatible).

5. Check for Leaks

• Reconnect the battery.
• Start the engine and let it idle, shifting through all gears.
• Inspect for leaks around the pan and seals while the vehicle is running.