Can 4.0 sohv k vin replace 97 ohv?

[Gabcar8321]

Hey everyone,
i have 2 explorers, 2004 explorer w/ sohc 4.0 with 80k original miles vin k 2wd
and a 1997 explorer sport w/ 4.0 ohv 2wd. With 165k original miles.

both start and run perfectly but have a couple of issues, the 97 has sat for years, rear main seal leak, lifters clatter, engine most likely needs to be rebuilt.
the 04, i was dealing with a Coolant leak and ended up overheating the Tranny (oops) and got one from a junkyard. And it needs a whole new front suspension

I was wondering if its possible to put the 2004 4.0 in the 97.
Will the transmissions be able to swap aswell?
i’ve read a bunch of threads but they only swap the ohv in with 02-03 engines. Why not the 2004-2005? Is it because of the Flex fuel thing? Is there a way to erase the flex fuel software for it to work?

neither are my Dailys, i just want to clear some space, get rid of sitting cars and have something to do this summer.

thanks, all feedback is appreciated

 

[410Fortune]

possible yes
bolt in deal, ,kinda
It has been done before. The SOHC engine will fit the 97 explorer
You can run a SOHC engine using a OHV engine computer

You would probably need a bunch of parts to put 04 engine into a 97
For one example the fuel system:
97 is return style fuel, 04 is returnless, that is one obstacle to overcome, not real easy either because 98 sohc fuel rails are hard to find, so the sport can be converted to use returnless fuel.

The 04 engine would then probably blow up your 97 auto trans in short order.

how much time and money do you have to spend on this?
Have you ever swapped engines before? pulled transmissions? Or how much experience at this stuff do you have?

 

[Gabcar8321]

running the sohc with the ohv computer will involve some rewiring right? Will the key system/ ignition/ anti theft become issues?

Also, the 04 tranny won’t fit then? The tranny on the 97 isn’t the good in condition either
I dont mind using 04 parts. The more the better. As for the fuel rail, ive seen tons of explorers in junkyards near me. I may have a chance to find them.

I’ve got unlimited time, not sure about unlimited money (obviously i dont plan on spending hundreds and hundred on this, and no experience doing engine swaps. I figured this would be a good start since theres no fabrication required? ( i don’t know you tell me)

possible yes
bolt in deal, ,kinda
It has been done before. The SOHC engine will fit the 97 explorer
You can run a SOHC engine using a OHV engine computer

You would probably need a bunch of parts to put 04 engine into a 97
For one example the fuel system:
97 is return style fuel, 04 is returnless, that is one obstacle to overcome, not real easy either because 98 sohc fuel rails are hard to find, so the sport can be converted to use returnless fuel.

The 04 engine would then probably blow up your 97 auto trans in short order.

how much time and money do you have to spend on this?
Have you ever swapped engines before? pulled transmissions? Or how much experience at this stuff do you have?

 

[410Fortune]

04 trans no go, its a different unit then the 97 5r55e auto you have now
Yes there is some MAJOR wiring on a few circuits, you would have to fool the 97 computer into thinking it is still running a OHV
This has and can be done, pretty easily in fact if you know what you are doing

There is no PATS security in a 97 Explorer, not until 98
With the 97 trans being no good you are back to square one, the 04 trans will not work in the 97

 

[Gabcar8321]

Alrighty, i see, so what do you recommend for a newbie like me? Is it a Good project to start out? Or Do you recommend to just avoid it? Im just a kid looking for something to do. And i really dont want to junk the 97 family is forcing Me Get rid of it If it just sits any longer.

04 trans no go, its a different unit then the 97 5r55e auto you have now
Yes there is some MAJOR wiring on a few circuits, you would have to fool the 97 computer into thinking it is still running a OHV
This has and can be done, pretty easily in fact if you know what you are doing

There is no PATS security in a 97 Explorer, not until 98
With the 97 trans being no good you are back to square one, the 04 trans will not work in the 97

 

[974X4BLACKSPORT]

Alrighty, i see, so what do you recommend for a newbie like me? Is it a Good project to start out? Or Do you recommend to just avoid it? Im just a kid looking for something to do. And i really dont want to junk the 97 family is forcing Me Get rid of it If it just sits any longer.

I would not recommend installing any other engine other than what exactly replaces the year, make model, and most importantly "calibration" for the vehicle in question. This means if your car came with an OHV 4.0L from the factory, replace with another OHV 4.0L of the same year and closest build date (FORD is know to making mechanical changes mid year in production). Put everything back to factory condition, fix broken wires and connections, replace broken or worn our hoses and pipes, ect. There are many sources to find the correct good used engine with a warranty.

 

[410Fortune]

that is correct, there are many places to get a good used 4.0 OHV engine
However you said the 97 auto trans is also not in good shape. Why would anyone put a good engine in front of a bad transmission? That is not spending money wisely. So you may want to consider a new/used engine AND a new used transmission or consider rebuilding the transmission.

Now with that said, this better be one nice 97 explorer in order to deserve all your money, time and attention like that! Some people really really love their trucks and want to keep them. They dream of how they want them to be and then they make it so.
The truth is a 97 Explorer was available with 3 drive trains and a few option. In 97 you could get a 4 door explorer with:
4.0L OHV and 5 speed manual
4.0L OHV and 5r55e automatic
4.0L SOHC and 5r55e automatic
5.0L OHV and 4r70w automatic

Any of these drivetrain combinations will "bolt in", meaning they are viable options for anyone looking to keep their truck.
However converting from one to the other is not exactly easy and there are several ways to go about this, this is why we classify these as drivetrain conversions.
A conversion is not exactly something you recommend to a newcomer.... but then that never stopped me some 25 years ago when I was asking how to re power a 1988 bronco II and the answer was "get a Jeep"
We can all see how that turned out. I picked my battles and I won, I never accepted no for an answer and now 25+ years later I am still driving that 1988, built exactly the way I wanted it. It did however get most of my time and money, so just know what you are getting into a why

SO you have a couple of options to think about, whenever people ask these questions about the best way to "repower" your old beloved 97 sploder, I ask them what do they intend to use the truck for? and then we go from there......
The stock engine, transmission and transfer case combo is not always the best path forward.
I know I wanted to keep my Bronco forever.

You are here asking the right questions, now you just need to do some research and decide the best path forward for you and your 97.
We are here to help you make a good solid informed decision

If it was my truck and I wanted to keep it forever I would be looking at two options:
4.0 OHV with a 5 speed
5.0 OHV with 4r70w automatic
but that is no secret as I custom build these trucks in my shop downstairs and when I do I focus around those two drivetrain options......they are my personal favorites for these trucks and with good reason.

Hope this helps!

 

[Gabcar8321]

Thank you everyone for your honest and reliable feedback. I guess i have some thinking to do

 

[Mbrooks420]

I’d do a quick search in your area for a 5.0. The values are down, and everyone is buying newer cars right now, for some reason. It’s a way better platform to start with, ESPECIALLY if you want to drive it hard. You could probably get into a V8 for a little more than a solid replacement 4.0.