Checking/topping up oil level in automatic transmission (AISIN GA8G45)

Precondition 

Vehicle in horizontal position.

• Shift the selector lever to the "P" position.
• Secure vehicle to prevent it rolling.
• Connect diagnostic system.
• Release oil filler plug (1) with Torx T55.

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• Release oil filler plug (1) from engine compartment.
• Release the banjo bolt (2) on the bottom of the transmission.
• Top up the automatic transmission fluid on the oil filler plug (1) until oil leaks on the banjo bolt (2).
• Start engine and run at idle speed.
• Check if the automatic transmission fluid is leaking on the banjo bolt (2).
• If no automatic transmission fluid is leaking on the banjo bolt (2), fill up the automatic transmission fluid on the oil filler plug (1).

  Courtesy of BMW OF NORTH AMERICA, INC.

• Actuate the foot brake and shift through all the gears "P" to "D" twice for more than two seconds at idle.
• Shift the selector lever to the "P" position.
• Check again whether automatic transmission fluid is leaking on the banjo bolt (2).
• Check the temperature of the automatic transmission fluid with the diagnostic system.
• Increase temperature of automatic transmission fluid to 35°C to 45°C.
• Top up automatic transmission fluid until it flows over.
• Replace sealing rings.

  Parts:  Sealing ring

• Screw in the oil filler plug (1) and the banjo bolt (2) and tighten it.

• Open the oil filler plug (1).
• Slacken the banjo bolt (2).
• Start the engine and let it idle until the transmission oil temperature is between 35°C and 45°C.
• Unscrew the banjo bolt (2).
• Check if the automatic transmission fluid is leaking on the banjo bolt (2).
• If no automatic transmission fluid is leaking on the banjo bolt (2), fill up the automatic transmission fluid on the oil filler plug (1).
• Top up the automatic transmission fluid until it overflows on the banjo bolt (2).
• Actuate the footbrake and at idle shift through all the gears "P" to "D" twice for more than two seconds.
• Shift the selector lever to the "P" position.
• Check oil level again.
• Replace sealing rings.

  Parts:  Sealing ring

• When the oil filler plug flows easily from the banjo bolt (2), tighten the banjo bolt (2) and the oil filler plug (1).

Precondition 

Vehicle in horizontal position.

• Shift the selector lever to the "P" position.
• Secure vehicle to prevent it rolling.
• Connect diagnostic system.
• Release oil filler plug (1) with Torx T55.

  Courtesy of BMW OF NORTH AMERICA, INC.

• Drain automatic transmission fluid: 
• Release banjo bolt (2) with Torx T40 on transmission (3).
• Release the oil drain plug (1) with the hexagon socket 17 mm on the transmission (3).
• Drain automatic transmission oil.
• Replace the sealing ring.

  Parts:  Sealing ring

• Tighten oil drain plug (2).

Courtesy of BMW OF NORTH AMERICA, INC.

• Add automatic transmission fluid (automatic transmission fluid has been drained off): 
• Release oil filler plug (1) from engine compartment.
• Release the hollow bolt (2) on the transmission below.
• Fill up automatic transmission fluid at the oil filler plug (1) until oil leaks at the banjo bolt (2).
• Start engine and run at idle speed.
• Check if the automatic transmission fluid is leaking on the banjo bolt (2).

  Courtesy of BMW OF NORTH AMERICA, INC.

• If no automatic transmission fluid is leaking on the banjo bolt (2), fill up the automatic transmission fluid on the oil filler plug (1).
• Actuate the footbrake and at idle shift through all the gears "P" to "D" twice for more than two seconds.
• Shift the selector lever to the "P" position.
• Check again whether automatic transmission fluid is leaking on the banjo bolt (2).
• Check the temperature of the automatic transmission fluid with the diagnostic system.
• Increase temperature of automatic transmission fluid to 35°C to 45°C.
• Top up automatic transmission fluid until it flows over.
• Replace sealing rings.

  Parts:  Sealing ring

• Screw in the oil filler plug (1) and the banjo bolt (2) and tighten it.

• Check oil level (transmission oil temperature must be between  35°C and  45°C):
• Open the oil filler plug (1).
• Slacken the banjo bolt (2).
• Start engine and run at idle speed.
• Unscrew the banjo bolt (2).
• Check if the automatic transmission fluid is leaking on the banjo bolt (2).
• If no automatic transmission fluid is leaking on the banjo bolt (2), fill up the automatic transmission fluid on the oil filler plug (1).
• Top up the automatic transmission fluid until it overflows on the banjo bolt (2).
• Actuate the footbrake and at idle shift through all the gears "P" to "D" twice for more than two seconds.
• Shift the selector lever to the "P" position.
• Check oil level again.
• Replace sealing rings.

  Parts:  Sealing ring

• If the oil leaks slightly from banjo bolt (2), tighten banjo bolt (2) and oil filler plug (1).