Crate engines were almost always manufactured and assembled off shore... where the costs were so much less expensive than in the US and the manufacture of the car could provide a new complete replacement engine under warranty for less then the cost of rebuilding an engine here... .
Today's very high quality manufacturing using CNC machining centers and robots to do a lot of the work in the machining process and measuring process means fewer failures and longer lasting engines... . So that program has gone away... .
BTW this was never done with any Diesel engine except the Chevrolet cross over, what ever that early diesel was.....
I've owned many trucks over the past 15 years... and we run each for 500K miles, which to us is when the body is worn out... . we've not had an engine failure in all the Fords and Dodges... we use regular oil and other products but DO follow a schedule that is 10K miles on the light trucks and 25K miles on the heavy trucks... .
Except for injectors and wiring harness issues on the Fords, I liked them... . I really liked the truck... But the Dodges so far have been more cost effective to own... with the same care... . and I'd never just let someone put a set of injectors on... ...
We do have extra filters on our stuff, fuel, and transmission filters on the Automatics...
As an example we don't just change the antifreeze, we test it, and add back an additive every year... . we've never lost a water pump on the Cummins... . if we change a hose we add back only distilled water...
I guess after all I've said... I really mean just drive it, take reasonable care of it... . and put it to work... . it will do the job...