I have a 2003 Ford ranger 4.0l 4x4 and the timing chain is probably gonna go soon and I am gonna start looking for a new 4.0l and I don’t want to deal with the chain again and I am wondering what year motor I should be looking for?

 

2004 and up should be OK
1997 to 2003 were problem years, but late 2003 might be OK

They only updated the tensioners on the longer chains, Passenger rear and drivers front
Those were the problem and it was not 100% failure rate so they didn't recognize it as a problem at first.

If you change the tensioners and timing chains(cassettes) on a 1997 to 2003 4.0l SOHC it will be the same engine as 2004-2012.
So never was an engine design issue.

From what I have read the springs used in the original tensioners would fail, get loose, this allowed the longer chains to bang on their guides at start up, oil pressure would keep them tight after startup.
The banging would break the guides over time and you would hear a rattle, at start up and then mid-RPM, at that point you needed to replace chains and guides(cassettes) and tensioners.


If you buy a 2001 to 2003 Ranger and engine does NOT have the rattle then replacing the tensioners will prevent future problems.

Unless your engine is a very high miler then I would keep it and replace the timing chains.
A used engine can still have that problem, running low on oil or not changing oil can cause the same issue on 2004 and up.
And used engine can have other problems, warranty doesn't cover labor to pull and reinstall the used engine.

So better the devil you know if current engine is OK except for timing chain rattle