Is it possible to put a 5.4 engine in a 4.6 configuration? (2004, F-150, 4x4, xlt, 8 ft bed)
1. what else needs to be altered, Trans? W-harness?
REASON: Have owned a 97 w/5.4 averaged 14 mpg (happy) bought a new 2004 but couldn't find one with 5.4.in Heritage configuration.Have been told they didn't make them with 5.4 in 2004 (8 ft bed) Now, 7-11 miles per gallon with 4.6...and gutless.(very unhappy) Should I just sell it and buy a used 2003, problem is, I like lower sides on bed of Heritage truck, easier to load tools. What were the designers thinking w/ 2005 higher bed? Thanks for response. BF

 

It is possible - just ask JMC - he did it. It's a ton of work though because there's more than just the engine to swap out. There are a ton of other things different between a 5.4 and 4.6 - like a bigger rear axle. From a work involved and resale value perspective, you might be better off trading.

 

You have a brand new 2004? Ok, it can be done. Find a 5.4 remove the 4.6 and install the 5.4. Use the harness from the 4.6 that you already have. Your 4.6 is most likely a Romeo (vin didgit #8 = W) so make sure you get the flexplate from a 5.4. You will neet to lengthen the oil pressure wire and the IAC wires. You will also need a chip to control the engine properly. Contact Mike Troyer. He is Superchips distrubutor in the computer forum.

If you have any more questions feel free to ask.

JMC

 

You know I like the bedsides being higher then the last generation truck. The designers did a good job IMHO. I can put my hunting stands in my 04 with the tonnau cover still on the truck, couldn't do that with my 98 because the sides were not tall enough. Same goes for my 5 gallon buckets with ice fishing junk. Now I can put the buckets/ ice auger in the truck and now worry about the height of them. Different strokes for different fokes.

 

BFleeson,
What rear ratio do you have. I bet the 97 had 355's and now you have like 310's. I know it doesn't make since but many get better milage with higher ratio rears. You also get more *****. With a rear switch and a custom tune (for your 4.6) from Mike Troyer I bet you get the same performance out of your PI 4.6 and probably compatable if not better milage. I think the truck is just too heavy for the higher ratio rears and you are just too deep into the throttle around town.
Any way you decide, I think it would be cheeper (and easier) to bolt on a supercharger then changing out the engine.
Good luck.