How to Replace the Transmission Fluid for a Mercedes-Benz 9-Speed Transmission?

1 Answers
LaKiara
07/30/25 10:26am
Method for replacing the transmission fluid in a Mercedes-Benz 9-speed transmission: 1. Secure the vehicle on a lift and remove the central and rear underbody panels of the engine; 2. Use tools to detach the quick-release locks on the oil pan—the transmission fluid filter should be replaced along with the oil pan; 3. Add approximately 6L of transmission fluid to the transmission. If the transmission is completely drained, about 10L of transmission fluid will be needed; 4. Clean the oil pan and reinstall all removed components. The 9-speed automatic transmission is an electronically controlled automatic transmission, consisting of 9 forward gears and 1 reverse gear. The gear ratios for each gear are achieved through planetary gear sets. All transmission functions and control components of this automatic transmission are integrated within a single assembly module, with the fully integrated transmission control unit located inside the automatic transmission, thereby reducing the number of vehicle wiring harness interfaces.
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