4.0l OHV was used in a few Ford vehicles, Rangers used them from 1990 to 2000.
Vary reliable engine, change the oil and keep the cooling system in good order.
The one flaw they have is a weak spot in the head between the valve seats, if engine is overheated that weak point will crack and you will have to replace the head.
So at the first sign of high temp.............pull over!!!!
Do NOT try to "make it home" or any where else
Let it cool off and then drive it......a short distance, it will save you a few hundred dollars, may be more.
The M5OD-R1 transmission is a good one, check fluid level when changing the engine oil
I am at 350k on my '94 4.0l manual.
Clutch, tires and brakes are about all I have done, besides oil.
I finally changed the spark plug wires 2012, original motorcraft, put another set in, hoping it keeps running for another 18 years.
I do put a can of Seafoam in gas tank for each of my vehicles once a year, seems to make them idle better and a little better MPG but never documented any of that, lol.
In 2001 Rangers got the 4.0l SOHC engine, no relation to the OHV engine, these had timing chain issues, but after it was repaired they also have a good track record.