School bus 7.3 into Ford F250

CaseyC · 01-19-2021, 08:14 PM

Hey everyone. I'm picking up a 7.3 from an International bus this weekend and am going to drop it in my Ford F250 that had the 5.4 gas in it before. My question is the wiring harness from the bus has 2 big plugs that go threw the fire wall to operate the instrument panel. Will those plugs fit my guage cluster in the F250? I read on here somewhere that I should get a Ford PCM and others said not to. I am using my 4R100 trans that my truck already had and placing it in a "shell" of a 7.3 4R100 to bolt up. Thank you for your time

ISAF2009 · 01-19-2021, 10:02 PM

You need a ford Ecm And about half the harness, and probably the turbo and maybe sensors The long block is identical but the sensors may not communicate with your ford ecm because the pigtails may be different. I would buy new sensors for the ford application and get a ford witing harness and ecu. The bus ecu may be governed differently and will not talk to the 4r100. Depending on the ecu you get you may have issues with the wastegate and the ebpv on the bus turbo. This is unfortunately not as plug and play as taking a long block out of a bus and replacing it in a truck that was originally equipped with a 7.3.

rossvtaylor · 01-19-2021, 10:07 PM

ISAF2009...you just impressed me! I read the OP's post and thought...now, who knows about both that particular bus AND that particular truck, and the interface of the two.

ISAF2009 · 01-19-2021, 11:35 PM

Ive been playing with these things since I was a kid unfortunately.

RamRod4 · 01-20-2021, 06:42 AM

Good luck Casey. That swap is not as straight forward as you'd think. But hey, at least you're getting rid of that 5.4. Good news is that the 5.4 has a neat weight reduction feature accomplished by ejecting spark plugs out before removal.

s2mikon · 01-20-2021, 08:49 AM

RamRod4, That is not a weight reduction feature. That was Fords highly successful audible "Check engine light" warning for drivers that ignored the light.

ISAF2009 · 01-20-2021, 01:21 PM

I’d rather they spit them out rather than the 2 piece plugs that break

CaseyC · 01-20-2021, 06:42 PM

Thank you for your help. Yeah 5.4 did the job until it swallowed a valve haha

CaseyC · 01-26-2021, 09:42 AM

I'm new to the forum thing, I asked the question bellow in a different section. I didnt realize it showed up different times. So I just copied and paste the other thread back to the original message. So we decided to transfer all computer and wiring from bus since I dont have a donor truck. Thank you

I am dropping a 98 International T444E 7.3L in my f250 that used to be gas. I am transferring all PCM and wiring over from bus. I am using my 4r100 transmission by putting my internal pieces into a 4r100 core 7.3 that will bolt right up to the international 7.3. So my question is in the computer of the allison transmission from the bus. Does the allison transmission run off the PCM of the bus or does it even have a computer? 2nd question will my 4r100 communicate with the bus PCM? If not I've talked to a company called US Shift that provide stand alone transmission computers but their concern is the PCM from the bus trying to communicate with the allison and its not there so will that cause any issues. Thank you for your time

ISAF2009 · 01-26-2021, 09:49 AM

No they will not communicate, nothing on that ford will communicate in any way with the bus PCM that means no guages, nothing. why don’t you just get a pcm and harness from a junkyard powerstroke?

CaseyC · 01-26-2021, 09:57 AM

Those trucks are popular where I am, none to be found. Even people "parting out" say that stuff is gone instantly. I can buy an IDM, ECM, and harness on ebay individually for a total of about $800 to a thousand. I dont mind doing this but I didnt want to spend that kind of money and everything not work out. Some other people that I read on other sites were saying the ford harness and all wont hook up to the t444e and others say it will. Another reason some people were saying the turbo had to be swapped but I didnt understand why since it faces the right direction. I know the international doesnt have a wastegate but most people disconnect those anyway. If I went with the Ford route what all would I need besides the idm, ecm, and harness? (My pedal now is cable driven and a 7.3 uses a tps)

ISAF2009 · 01-26-2021, 10:09 AM

The pedal is a problem. Most 7.3 people get rid of the ebpv not the wastegate . You will need a harness, IDM, ecu and maybe all the sensors as the international may have different connectors.

CaseyC · 01-26-2021, 10:15 AM

Do you know where I can find a wiring diagram for the ford harness? I've tried to google it but nothing solid showing just what each piece of the harness connects to. Thank you for your time

ISAF2009 · 01-26-2021, 10:17 AM

Get an alldata DIY account

CaseyC · 01-26-2021, 10:18 AM

Ok I'll look into that. Thank you

Unpluggedone · 01-30-2021, 08:21 PM

How many miles on the 7.3?

Mountain Gnome · 01-30-2021, 10:18 PM

Quote:

Originally Posted by CaseyC

Do you know where I can find a wiring diagram for the ford harness? I've tried to google it but nothing solid showing just what each piece of the harness connects to. Thank you for your time

I got a library card and that gives me free access to Chilton online. They usually have wiring diagrams for any vehicle that is not TOO old; but very new vehicles may not even be listed yet.

Bluebird69 · 01-31-2021, 01:33 AM

Quote:

Originally Posted by ISAF2009

Ive been playing with these things since I was a kid unfortunately.

ISAF2009 I have a question for you then. If you don't mind me asking.
I have a 1990 international bus, bluebird body and a 7.3 IDI. My question is how/where do I remove/change the governor? I just purchased my bus over the summer and am slowly working on it.
Thank you for any input.

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