I have a 98 5.4L f150 that needs the motor replaced.. found an engine out of a 02 f150 that is also the 5.4L. will it fit? The guy said it would only fit 02-04, but i wasn't sure if that was correct. Thanks!

 

Yes, like a glove.

 

Here's what you should know -

Yea, the only things different. The O2 has PI heads. The 98's have Non-PI (Power Improved). Not a problem, I mean you can tune the motor to get it perfect, but you really don't need to. You'll have about 20 more HP w/the 2002, might leave about 5 hp on the table without tuning or dialing in.

Also, the DPFE Sensor is different. That's easily overcome, use the 98's set up.

Use the 98 harness unless it's in bad shape. There's really not much to this swap. There may be little differences (very little) on the 2002 intake manifold, - it's plastic vs aluminum. You have to use the 02 manifold. The rectifiers might bolt to a different local, along with the firewall ground strap. But yea, like I said, very small differences that's easy to deal with.

Any and all "TRUCK" engines are basically interchangeable from 1997 -2003 and some 2004's. The very best you can do is find a late model 2003 or 2004 2 valve 5.4L. For these engines include the latest heads revisions from Ford which entail 8 thread plug chambers compared to 4 thread plug chambers.

That's the scoop.

Good Luck

 

So, you're basically saying for my 98 4.6L, I could go out and find a 2002-2003 4.6L and it's a direct swap?? Wouldn't I not use the newer PCM too with the swap?

 

You use your original PCM. Even if you upgrade to a 5.4L.

 

The exhaust will mount up but there is a good chance the flanges are a hair wider on the 02. Which like I said will mount and is not that noticeable. What you have to watch out for is the long term stress it may apply to the manifolds, causing premature exhaust leaks. Shouldn't be an issue though. But... if you can get the y pipe from the donor then even better. Like Jbrew said, the rectifiers may mount in a different location, no biggie. And the manifold to firewall ground strap. If you are going to keep your AC (if you have it) you may have the 6 rib belt and they 02 engine may have the 8 rib, or is it the other way around? I forget, but you may have to swap a few pulleys around. Other than that... direct swap.

 

Isn't there a torque converter stall speed issue between the 4.6 and 5.4, and don't you need to retune the PCM?

 

torque converter stays in the transmission, so no need to retune it since you are keeping your same TC and PCM

 

You still keep your original PCM, you have to re-tune it going 4six to 5four to get everything perfect, -from what I understand. You can run it, but it's not advisable. Specially if you swapping the bigger V8 into a 97-2000 model year that had a 4.6L previously. The 01 + 4six has a slightly different tune.

Now, -I guess there's an easy way or write up out there instructing how to go from coil packs to a COP system. Don't know all that much about that yet, just that it's doable if desired.

 

Yea, but the TPS is involved there as well. MAF - TPS - TRANS, right... So, if all that is tuned for the 4six, it seems that some adjusting needs to be done in order to take advantage of the 5fours curve. Isn't that right ? The trans shares with RPM info (engine).

 

true, but i was specifically referring to the torque converter aspect