The Mercedes-Benz Actros uses several different V6 diesel engines over its production lifespan, and therefore there isn't one single firing order. The firing order varies depending on the specific engine type and configuration. There is no standard "running mate" in the sense of a specific engine always paired with another.
To find the correct firing order, you must identify the exact engine code (found on an engine plate usually located on the engine block itself). Once you have the engine code, you can consult the Mercedes-Benz service literature or an online database specific to Mercedes-Benz engines to determine the correct firing order.
