There is a much lower incidence of rod problems with factory replacement engines. I should say there is a lower incidence of problems in general since I'm not personally aware of a failed replacement engine that was taken apart. I've heard of a couple of cases of factory replacement engines developing telltale oil consumption. Factory replacement engines come with a considerable warranty though I imagine it's not transferrable.

How long ago was the engine replaced? What documentation supports this?

Out of curiosity, what is the replacement block serial number?

Early 140s have persistent problems not related to the engine so don't sign-off on the rest of the car just because the engine checks out.

Sixto
93 300SD