Way off topic.... 5.4L to 4.6L swap in a F150......

[64PI]

Does anyone have any experience in going from a 5.4l to a 4.6l? Here's the back story.... My dad has a 2005 F-150 4.6L 4X4 he bought new. Plain Jane no power windows, locks, vinyl floor mat, etc... Upstate NY winters have taken its toll on it for sure.. The box looks like swish cheese and cabs showing the same signs. But amazingly the frame is still in nice shape and the engine runs like a watch. So he recently just bought a 2004 FX4 F-150 with a grenaded 5.4L 3 valve engine. The frame is totally shot on this truck BUT the cab and all other sheet metal is pretty nice. Plus this cab has Power seats, windows, locks, sliding rear, Cd and Cassette player(I think that's why he bought it).   We're thinking about taking the nicer cab and putting it onto his frame and drivetrain. I am going to assume its going to be a wiring nightmare. Will the 4.6 engine harness plug into the 5.4l pin connector? Will the computer need to be reprogrammed? I've searched truck forums and had no luck getting a straight answer.. Just guys bashing the 4.6 and saying the 5.4 3V is the best engine ever! Any advice is appreciated.. Just trying to help my dad out.

Fred

[e philpott]

is the 4.6 a 3 valve ?

[Falcon67]

I had a 4.6L at one time and from talking with people that know, a swap to a 5.4L would require ripping the truck apart.  Motor, matching harness, computer.  So I'll say No- you cant just plug in the cab and computer.  You will likely need a cab harness and matching computer.  All the accessories make it worse.  From what I do know about the 4.6 and 5.4 is that parts do not necessarily interchange.  The old 4.6L developed a crack in the oil filter adapter.  Arrow Ford had to order all 4 adapters (under warranty thankfully) before finding out that the factory used a 5.4L 4x4 part on a 4.6L 4x2 application.  It can also depend on which plant the engine came from. 

Stick with the 5.4.  It's a nicer motor IMHO anyway.  My 2004 has 139K on it and runs just fine.