First, to start the diagnoses given the fact that it is an automatic gear system, check the color of the transmission fluid. It should be dark red but in case it is black, then it needs to be changed together with the oil filter. After that, check the level while the gearbox is warm. Also after the selector is moved through all the gear positions, making sure it is maintained at each gear for at least few seconds before returning to the “Park” position. The box can be filled via the dipstick tube if need be. Ensure to use the correct recommended oil. This is imperative on the Mercedes Actros since fluids for cars vary. However, some producers may recommend a change in the type of fluid. Confirm with the local dealer or parts department to get the information on the updated fluid to be used.
If examination of these indicates that this aspect is fine, the electrical connections of the gearbox should be checked. Individual connector should be removed and sprayed with contact cleaner.
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