The 431 bleeding method is used for Mercedes Benz E300 transmission: step on the clutch for a few feet, then step on it to the bottom, open the screw at the exhaust port of the cylinder and tighten it after exhaust. Then step on the clutch and loosen the cylinder screw to exhaust. Repeat the process and add oil until the air is exhausted and the liquid level is stable within the range required by the marking
 How to bleed with 431 for Benz E300 transmission
 At the lower rear of the water tank, in front of the gearbox (looking at the whole engine compartment), a black pipe runs into the gearbox. There is a leather cover at the connection. Open it. Before that, the brake oil cup was full of oil.
 Next, there is a snap ring at the black oil pipe. Press it to the bottom, then pull out some of the black pipe, but do not pull it out. Wait quietly to see the bubbles coming out of the oil hole. When there are not so many bubbles, press the pipe in, and the snap ring will automatically return to its original position. Then press the clutch pedal several times, press it, and pull out some of the black pipe, Continue the process of bleeding and step on it several times.