Anyone have any info or knowledge to share it would be appreciated. I have a 2005 expedition limited with a 5.4 V8 motor. 4x4 4 speed transmission. Has a locked up motor. Just wondering if I would have to have that exact motor or if the 4.6 would fit? I heard it might but the electronics may not. And also if the 4.6 did work would I have to swap the tranny to match that?

 

Being a 2005, you should have the 4R75E automatic transmission. Both the 4.6 & 5.4 were available engines, so I would gather that the 4.6 would bolt up to the transmission. Your only other issue would be the electronic controls difference between the 4.6 vs the 5.4 engines

 

Previous years allowed engine swaps without too much problems. Keep in mind you are going to have a smaller powerhouse to move a big bus and expect it will have to work harder to do what the 5.4 did. If both of those engines were available for that model year it might be possible without too much trouble. You definitely will need the PCM from the 4.6 and that opens a whole new can of worms. The PCM is programmed to each particular vehicle and the anti theft system will not recognize the new PCM and that is where the fun begins. The vehicle won't even start without a capable scan tool to program the replacement PCM to your vehicle. Do you know any history from the vehicle that the 4.6 PCM came from? If it has had any problems , they are now your problems. There could be more and I'm sure I didn't cover everything, but I would give this some serious thought and do as much research as you can before taking on this job.