I was wondering if someone could help me I am swaping out a 4.6 to a 5.4 .I had 01 f150 which I rolled on its side engine was good but locked up cause of the roll over jumped timing and bent valves. I bought an 03f150 with a 4.6 with a good body and plan on buying a 5.4 crate engine to put in the 03 with the good body I already swapped transmission from the 01 cause I know the torque converters idle speed is different on the 4.6 and 5.4. I also know that the computer has to be flashed over with dash and ignition which I already did i switched dash and computer and ignition switch that was in the 01 to my 03 I'm waiting to buy the crate engine now which will be a 5.4 my question is do i need the wiring harness from the 01 to put in the 03 to work since it had a 4.6 and if there is anything else I need to swap out so the 5.4 engine will work in my 03 also what companies sell good crate engines. Thanks in advanced would really appreciate the help

 

Power train on the 5.4 or 4.6 engine with a five-year unlimited mileage warranty. They come set with all you have to do is place valve covers on and intake plus your alternator stuff like that with all gaskets and a high-pressure oil pump by mil. (Last time I checked they were around $2,700 with your old engine core Jasper was around $6,000 and others were around $3,000 up)
You can do what you want, but I will never buy one from Auto Zone, Advance, and those auto parts stores or the Jasper engines after having to fix their engines and them not standing behind the warranty or any of that. The wait time is unreal to get money from them or for them to ok a fix if they ever do.

Exhaust pipe angle or something like that from a 4.6 to a 5.4. You need to check that as I can't remember.

You will need a new torque converter for the 5.4 as that 4.6 one will not hold up as you would want in an everyday truck. (Yes I know the Stang people love to make those types of torque converter hookups and others.) Also the transmission wiring harness depending on which one was in what truck and flywheel.

The wiring harness is the same on the 01-03 for both engines with the Romeo 4.6 D24D heads (which is their PI heads) and Wins 5.4 PI heads. With that said, if the old engine is Wins 4.6 you will have to use the 03 engine wiring harness as the Wins is an NPI engine. The engine wiring harness and PCM don't care as the PATS is not part of the engine harness. The Pats just kill the firing side as they are both the same.
(To know which one you have look on the passager side of the head at the front by the exhaust manifold just above for either the Romeo D24D heads or a blank Wins with just numbers) 2001 was the first year of the PI heads on a 4.6 and they only came with the Romeo engine in an F150 (Note some early trucks did not get the Romeo engine) and not a Wins engine. Or just look at the Vin number of the old truck for the W Remeo and 6 Wins engine.

The PCM has a different fuel set up for 4.6 and 5.4 and a different limp mode as well, but not by much. Is your new 4.6 truck have an EGR valve or the old one? That will be the question they will ask as well.
You can call those companies that rebuild the PCM's and ask them what has to be flashed or not flashed.

 

They are both winsor engines. The 01 was the one with the 5.4 the 03 had the 4.6 and is the one I have changed the computer the instrument cluster and ignition from the 01 so it will be ready for the 5.4 crate engine they both have the egr valve I also have all the exhaust from my 01 that had the 5.4 I already swapped the tranny and tourque converter even though they both have the 4r70w but I knew about the tourque converter change and honestly don't know if the tranny on the 03 works which is another reason I changed it cause the 03 I just bought cause the body is good and originally was going to change my 5.4 from my 01 after it went on its side but engine ended being Locked up so I have decided on a crate engine now. I really wasn't sure about the wiring harness but today I took it off the 01 and compared it to the 03 and they are identical so I guess I can use the 4.6 harness. The heads both say PI on them also. As far as power train I have researched them and they seem good I just have never bought a crate engine from any company thanks for the advice greatly appreciated

 

I know some Fords got the 4.6 2v Romeo D24D engines in 2001 and that all F150 that had 4.6 engines in 2004 until late/early 2009 got the 4.6 2v Romeo engines. In 2010 they Ford put those 4.6 3v engines in F150 up till they said no more.