4.0 engine swap

[brownmule]

My daughter wiped to passenger side of my 96 regular cab 4.0. I had just rebuilt the top end. I found a 97 4.0 extended cab truck with engine problems. My question is can I swap my engine into the 97 extended cab? Is the automatic transmission the same with a longer drive shaft? Is there a headache in the harness switching 96 into a 97? I'm wondering if this is feasible, my daughter just started driving and loves the truck Please advise. Thanks for the help!

 

[franklin2]

Do some searching and more research on this. I think a 4.0 is a 4.0, but on the interchange on car-part, when I looked up a 96 engine, they only listed 95 and 96 engines, no 1997 engines. It may be something very minor that can be changed, but I am not sure about it. They list their engines as direct drop ins, so something is a little different about those two years.

 

[brownmule]

I see that flywheel is different and auto transmissions are different. I wonder how hard it would be to change PCM and wiring harness into the 97 and use the engine and transmission from the 96? Seems like it's like stuffing a 5 pound cat in a three pound can?

 

[franklin2]

Hopefully someone who knows more about the 4.0 changes will reply, but unless there is some major difference, I would think putting the 96 4.0 engine into the 97, but using all the 97 wiring plugged into the 96 engine would be the easiest. If the transmission is different, is the 97 transmission any good? If you could re-use that, you know it would bolt to the 96 4.0. Then there would be no wiring hassles or computer swapping.

There has to be something you will have to swap or change on the 96 engine to make it work in the 97 truck. I just don't know what it is.

 

[19Walt93]

Salvage yards always had an interchange manual that listed any parts that were different. We'd often get different year replacment engines and just transfer parts from the original.

 

[lil_Blue_Ford]

Supposedly there are changes internally that I’ve been unaware of on the 4.0 motors. I always thought a 4.0 was a 4.0 and treated it as such. My Choptop currently has a 95 or 96 Explorer 4.0 and it’s bolted to an FM-146 that was originally behind a 2.9, I just converted everything that bolts on to match the 91 Ranger harness and computer and away we go.

I’d just swap wiring and drop it in the 97. I’m guessing by trans differences it could just be a matter of something like A4LD to 4R44 or 4R55 or 5R55, but all four of them are similar, they all bolt up fine, just some different internals basically. Run 97 everything.

 

[brownmule]

How hard is it to take the PCM and wiring from my Good running truck and transplant it into the 97? Has anyone done that? 97 changed crank flywheel bolt pattern and a different style transmission. Did they also change the fuel injection routing? Donor truck motor / trans has issues. Is this swap viable option?

 

[brownmule]

Supposedly there are changes internally that I’ve been unaware of on the 4.0 motors. I always thought a 4.0 was a 4.0 and treated it as such. My Choptop currently has a 95 or 96 Explorer 4.0 and it’s bolted to an FM-146 that was originally behind a 2.9, I just converted everything that bolts on to match the 91 Ranger harness and computer and away we go.

I’d just swap wiring and drop it in the 97. I’m guessing by trans differences it could just be a matter of something like A4LD to 4R44 or 4R55 or 5R55, but all four of them are similar, they all bolt up fine, just some different internals basically. Run 97 everything.

 

[franklin2]

You must like messing with wiring and schematics. Are the beds the same length? I would rather buy the 97 and put the fender, the door, and the bed on the 96 rather than mess with all that other stuff. Keep the 96 all together. She may have another fender bender, so no use going to a lot of trouble most likely.

 

[brownmule]

Yes my thoughts as well. The striker jamb and the front cab door jamb are bent pretty good. Top hinge and striker cab corner mashed good. Maybe a cut off wheel, wire welder and torch is the low road. I did see a truck and hour and half away 96 bad trans, column out and console but 4.0 auto.

 

[bobbywalter]

well....as you have seen....these engines are indeed not the same. and change constantly and midyear sometimes.


in 96 the change to go full keyway in the crank with the timing gear started and then there was a step added because the nub they were using would not drive the overhead cam chain and gears.... even the crank bob weights and piston weight would change a bit later in 99 or so and in 97 the blocks were reinforced to reduce NVH and have fat pan rails and different sized dipstick..

the 8 hole cranks can be interchanged between sohc and ohv....you just have to make sure the right timing gears and bobweight/piston and rod matching is done.


so....internally....these things are a mess.


as far as the scope of what you are asking...

yes. swap the eec harness and ecm with the engines is usually the safe bet.. there are connector changes for some things.

in your case the 95-97 pretty much are the same in regards to eec, but late 97 into 98 there are differences....fuel systems also change and pats systems start ect....

i would just swap the engine.

this case sensor wise should be the same...the engine differences are all internal.

if there is somthing different...please list it along with your actual production date.

 

[bobbywalter]

Supposedly there are changes internally that I’ve been unaware of on the 4.0 motors. I always thought a 4.0 was a 4.0 and treated it as such. My Choptop currently has a 95 or 96 Explorer 4.0 and it’s bolted to an FM-146 that was originally behind a 2.9, I just converted everything that bolts on to match the 91 Ranger harness and computer and away we go.

I’d just swap wiring and drop it in the 97. I’m guessing by trans differences it could just be a matter of something like A4LD to 4R44 or 4R55 or 5R55, but all four of them are similar, they all bolt up fine, just some different internals basically. Run 97 everything.

that i know of...there are 3 pistons.....3 blocks.....like 4 cranks.....at least 3 types of rod...and you better weigh the fawkers....because measuring the weight pads assuming that they look the same and have the same numbers fawked me before...

heads.....yeah theres different heads. the fast burns can really fawk you depending on what you are building...


cams....there are 3 or 4 cams as well. these are auto to manual with some advance built into one over another....and depending on egr or non egr calibrations.

there is a reason i dont build 4.0s.

you can. you just have to pay attention and start with a complete system and keep it complete.

same as swapping one. i always suggest swapping a complete known functioning system because you can really get into trouble.

using the cammer computer to run a ohv and vice versa can work really good...or really bad depending on the specifics.

 

[franklin2]

Your posts are general info posts correct? His 1997 4.0 is not a OHC engine is it?

 

[bobbywalter]

Your posts are general info posts correct? His 1997 4.0 is not a OHC engine is it?

is that a question for me?


i assume the 97 is not a sohc.... iirc they start in 2001.

if it was not clear....in this case, 96 to 97 would be a rare situation i would just swap the engine.

the sensor package is very similar.

if there is a problem i would like him to report the different connectors and build dates.

i do think there were some transmission side changes thet wont matter if staying intact with system....the upstream and down stream o2 sensors and fuel setups are the same as i remember....but thats not good...i fawk up alot on memory.

that said i have swapped 99 to 96 and had issues with a 99....had to totally dress the long block with the 96 stuff. and found out the cam was different. but it worked.

 

[franklin2]

is that a question for me?

Yes. I should have quoted your post.