I have a 99 F150 5.4 ext cab that most probably will need the engine replaced. Can it be replaced straight up by a 2004 3 valve 5.4 or would it require modifications such as wiring harness, computer etc. Thanks for the help.

 

I do not think the 3v would work...

 

yeah will be complicated I dont think it will work. Just get another 5.4L and mod it up with heads and cam you can probably get it to 350 h/p

 

the 5.4 3v will work fine. there are a few mods, but it and all ford MODs will plug in. you will need a 75mm manual cable throttle body and adapter plate.

eliminate cmc plates, etc. your pcm will control it. no vct, but it will still make plenty of power.

the limit is probably 400 rwhp @ 6900 with appropriate forgings. without VCT. 2v is a joke compared to 3v or 4v. if you use it for towing, optimize it for that.

 

If it were me I would contact JMC or Neal, before doing the swap, they would know what would be required.

 

Thanks for the responses. I found a good deal on a complete used 5.4 3 valve engine and was hoping that I could just pull my seized 2 valve and drop the 3 valve in.

 

It wont be that easy. The computer and wiring stuff will surely cause you a few headaches.