2004 4.0 swapping engine

[Apexmaster]

Hi guys, my co worker donated her explorer. The driver side head gasket is blown and licking coolant. I have done research and looks like for that side to do a head job u need to pull motor out. This one currently has 210k on it and if I'm going to pull it out, I rather buy another used motor with lower miles and 1 year warranty.
I have done this before on a 99 Chevy S10 with the 4.3 v6. I also had to get the new ECM programmed in order to work with the truck.
Is this the case with the explorer or Ford in general? What other options do I have?

 

[Rick]

Of course the easiest route is to find the same year engine, and the same type, as in SOHC or OHV.

You can swap motors from different years, the only issue is the sensors on the engine. Most have swapped manifolds so that the sensors are all there and in the proper location.

 

[Apexmaster]

Yes, I'll be getting a same year model engine. I think the issue is when I buy the engine it comes with it's own ECM. Even though it's exact same model engine I need to code the new ECM to car.

 

[Rick]

I believe that with the Ford you need to keep the computer that came with the truck or you will have issues with PATS. I do not recall reading that folks had to reprogram their computers when doing a straight engine swap.

 

[Apexmaster]

great, what is PATS?
So use original ecu not new one that comes with the new engine

 

[Tshaw88]

I just did this back in April, swapped the motor out of my 05 with a 4.0 flex fuel from an 03. Just pulled both motors and basically stripped them down to the block and heads, then took everything from the 05 and put it on the 03, and dropped it back in the car. Had to swap the fuel injectors because mine was not a flex fuel but the donor engine was, intake manifold, throttle body, and valve covers. The valve covers were the same but I cracked one putting the motor back in. Wasn't too bad a job, didn't need to reprogram the computer either car ran great until the transmission blew up a couple weeks ago.