When I lived in Germany, in the 90s, I regularly sat in diesel Mercedes Benz taxis with over a million kms under the hood. Private drivers usually. Many had giant mileages. We used to say (tongue in cheek) that after 250k, the MB diesel engine was broken in. I don't think MB makes them like they used to anymore.
I recall a Greek 240D that had exceeded 4M kM (i.e. 4 GM). Regular motor and transmission rebuilds at intervals that would shame a contemporary dealer's service department.
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