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5.4 to 4.6 motor swap

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Old 07-19-2014, 08:50 PM
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5.4 to 4.6 motor swap

Im looking for all info possible in regards to swaping a 2002 romeo 4.6, which is in a 2wd truck, in place of a 2000 windsor 5.4 in a 4wd truck. The 5.4 needs work, as it is currently not running, due to having been run out of oil, but the 4.6 is running great. I am not worried about power loss, since I will not need the 4wd for anything more then snow travel. Please let me know if you have done this before or have knowledge of the necessary steps, and altrications that needs to happen to make3 this engine swap possible. For instance, harness swap, computer swap, timing chain cover, or flywheel/torque converter/transmission assembly connectivity.
 
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Old 07-20-2014, 09:59 PM
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The wiring harness should be fine the 5.4's is longer than the 4.6, the 5.4 timing cover will not work on the 4.6. I could be wrong but I think the 5.4 has an 8 bolt fly wheel and the 4.6 is 6 bolt. Also to the 2wd probably has a 4R70W transmission where as your 4wd probably has a 4R100 transmission so the torque converter will have to be changed. You need to check that. The 5.4 is physically wider than the 4.6 so your exhaust Y-pipe is going to have to be narrowed. It's do able.
 
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Old 07-20-2014, 10:27 PM
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This would be the first time doing anything of this magnitude so I'm asking...if I change out the entire motor, why would I need to change the timing chain cover? As far as the torque converter, would the one in the 4.6 combo do the trick. Thanks for the response and the info.
 
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Old 07-20-2014, 11:25 PM
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You mentioned the timing cover in your first post. As for the torque convertor I believe the 4R70W which is probably the tranny in the 2wd uses a different convertor than the 4R100, the converter from your truck might bolt up to the 4.6's fly wheel I don't know for sure. it's just one of those things to check on. The 2wd could have a 4R100, it depends on how it was optioned, just as your truck could have a 4R70W, it depends how it was optioned.

Something I forgot to address was the PCM, Your PCM will not run the 4.6. It will probably start but the fuel tables and timing tables will not be correct for the 4.6. The PCM out of the 2wd would run the engine but not the transmission, even if both have the same tranny your 4wd has a different shift timing and I would bet your rear end ratio is different which is going to effect the transmission and the speedometer. You will have to have your PCM reprogrammed. Also your keys are set to your current PCM so your stuck with that. I'm not sure if a Ford dealer could re flash your PCM to work with the 4.6, To get it done in the after market your looking at spending $400 to $500.
 
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Old 07-21-2014, 07:32 AM
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Ok, so if the 5.4 was rebuildable, that route might take less time and possibly less money in the long run? The story I get on the 5.4 is that it was run out of oil, due to an oil pan gasket leak, and that the bearings need replaced. I dont know of anymore damage till I have it checked out.
 
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Old 07-21-2014, 06:34 PM
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It would probably be easier to either fix your 5.4 or replace with a 5.4 out of the bone yard. If the 5.4 froze up while it was running it's going to need more than just the bearings replaced. I would almost bet the crank is toast a long with the mains and the rod bearings. Oil pump is probably done also. Ford uses powder metal rod in these motors, I would have all the rods checked by a machine shop, they are the weakest part of the engine. The machine shop should be able to magnaflux them to see if they have any stress cracks.

At this point unless your doing the majority of the work yourself, it would be easier and most likely cheaper to find a good 5.4 in the bone yard.
 
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Old 07-21-2014, 08:46 PM
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Thanks for the info. I was gonna have a shop look at it for me and rebuild it since my knowledge is not enough to do it myself. I appreciate all the time you have given up to post the information. Thanks again, and wish me luck, as I am doing this on a very tight budget.
 
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Old 07-22-2014, 08:19 AM
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Glad to help. Keep us updated on how the project progresses. Good luck.
 
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Old 08-30-2014, 07:35 PM
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I'm about to attempt a swap from 4.6 8th digit 6 motor to a 5.4 and I am needing to know which 5.4 I need for this process my 4.6 is a 2003 model motor and truck is automatic . I have read that I need To replace the torque convertor as well as the exhaust. What else would I need to swap out? Could I use the exhaust from a 5.4 truck out if a bone yard? Also I have a friend that will reprogram my PCM for free. I need a check list if anyone has done this and could shed some light on this process. Please. Thanks
 
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Old 03-05-2016, 12:40 PM
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help

I have a 1996 mercury grand marquis the original motor was a 4.6 but i also have and 1997 ford expedition with a 5.4 and i wanna know will this swap work answers
 
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Old 03-05-2016, 12:53 PM
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Engine computers are different. It will probably bolt up, but making it run will be a challenge.

IMO you are best served by sticking to the OEM replacement.

In some cases, you can swap in the long block and just replace the intake and exhaust with the original vehicle stuff. Pretty sure the 5.4 stuff isn't going to bolt up to a car 4.6 from the prior year.
 
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Old 03-05-2016, 12:59 PM
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Originally Posted by 85e150six4mtod
Engine computers are different. It will probably bolt up, but making it run will be a challenge.

IMO you are best served by sticking to the OEM replacement.

In some cases, you can swap in the long block and just replace the intake and exhaust with the original vehicle stuff. Pretty sure the 5.4 stuff isn't going to bolt up to a car 4.6 from the prior year.
So u dont think it will work
 
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Old 03-05-2016, 02:45 PM
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Originally Posted by Tking Thomas
So u dont think it will work
Knowing what little I do, I would find a guaranteed used or reman'd 5.4 for that year.
 
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