bthood

I’ve got a question I’d like to see if anyone out there might know the answer to. I’ve got a 2002 5.4 that’s throwing a rod. I happen to have a good running 4.6. It was in a Lincoln town car that was wrecked. Well I know that the 4.6 is a little bit slower with a little bit less torque than a 5.4 I’m on a tight budget and I’m all for using what I have versus what I don’t have to buy. Has anyone ever had an experience trying to swap from a 5.4 to 4.6? They’re both two valve engines and they’re both Romeos. I am aware that I’ll have to change the manifold, oil pan, exhaust manifold, and the starter. With all that being said, will this engine run in this vehicle? I know the transmissions in both vehicles are 4R70’s so I’m pretty sure that should bolt up. My biggest concern or I guess my biggest question to everyone would be this, since the computer from the 2002 originally in my truck is designed for a 5.4, and a 5.4 is a larger displacement, will there be a issue with the 4.6 being overfilled? I guess I could get the computer reprogram but that would be a whole Lotta extra money that I really don’t have at the moment. Has anyone ever tried any of this?

Johnny Paycheck

The swap would work. Get a 4.6 torque converter as well.

I believe a 5.4 computer will run a 4.6, but not certain how well across all driving scenarios. A tune would be nice to get if they can still be had for something this old. Otherwise, you need a truck 4.6 computer and have to reflash PATS to have it handshake with the cluster.