Hello, Must now have to the 3 year mandatory check now I had asked for transmission oil change but the workshop master told me that I should not have had to rinse until 180000 Km since Ford can not prescribe an oil change here that is I have the 6-speed automatic gearbox 6F55. Can this be??? Have currently 50000km Good morning Mr. Wenz, In your vehicle the 6-speed automatic gearbox 6F55 is installed. Ford does not prescribe an oil change interval here. The automatic transmission can be flushed between 180.000km and 200.000km. Unfortunately, a simple oil change is not enough here, since the oil can only be obtained from the converter by rinsing the automatic transmission. Sincerely, etc.