Good morning all! I apologize if this is the wrong place to ask, but im currently driving a 2005 Ranger 2wd auto (5R55E) with a 4.0 SOHC. I have started to notice what sounds to be a pretty significant rod knock so I have started looking in to a donor motor. A friend has made available to me a full running driving 1994 2dr explorer sport manual (M5OD) with a 4.0 OHV. The explorer is a registration nightmare with a lost title years ago, otherwise I would probably drive that full time. My question for you all is if you think that going from SOHC to OHV would be more of a hassle then it’s worth. The ranger is my DD so as little downtime as possible would be ideal. Iv done motor work in the past on 12V Cummins and OBS 7.3 Powerstrokes but never with the 4.0 powerplant and have access to full shop amd tools. Any major complications or areas of trouble? Thank you all for your time in advance!

 

Welcome to the forum

No, not a good swap, need full wiring swap and computer swap and dash swap
The 2005 is full digital OBD2 and 1994 is analog OBD1, it would be a wiring nightmare and alot of non-engine modules would be throwing codes all the time so tough to pass smog tests

And in Calif. you couldn't get it registered in any case
Calif. requires any engine replacements to be same year engine or newer

Look for a 4.0l SOHC 2005-2011 engine, to be legal
If you are doing all the work yourself then 2001-2011 4.0l SOHC long block would work, always replace the 2 timing chain tensioners on 4.0l SOHC engines
I wouldn't think "they" would check engine numbers, but....................
Swap over your 2005 intakes to match 2005 wiring for any year you get

Knock sensor and rear main seal are also good parts to swap with engine out

4.0l SOHC engine was used in these vehicles, in these year
2001–2012 Ford Ranger
2001–2010 Mazda B4000
1997–2010 Ford Explorer/Mercury Mountaineer
2005–2010 Ford Mustang

The 1997 to 2003 had timing chain issues, so best to replace those if you get one from those years, but ALWAYS replace the 2 long chain tensioners regardless and then do it every 100k miles after that, use Motorcraft only tensioners

 

Thank you for the quick response. That addresses all of my concerns.