Hello FTE,
I don't know much about these engines but I'm looking into buying a F-150 and I don't know what engine would be better to have.

Thank you,

Barry

 

It is the same base engine, 5.4L just has a longer stroke and therefore more power and torque.

 

They may be the same base engine, but, as I understand it, the 5.4 got the 3V head first. The 3V head has the infamous spark plug problems (early years blew out plugs, first fix made plug change a potentially expensive nightmare --finally fixed).

I just saw that later years of the 4.6 got this head and the spark plug problems that go with it.

hj

 

After about 130k I had the spark plug problem on my 2001 4.6l 2v. I have around 90k miles on this 2001 5.4l 2v and so far doing good. The problem there which exist's on both is that there is only like 3 threads for the spark plug in an aluminum head.

Putting that aside, I would go with the 5.4l imo just because it is more power and not that much different in fuel mileage. I have never heard anybody say they have too much power in their Ford truck.

Anyway, they are pretty similar motors trannys bolt right up (flywheels are not interchangeable), the "V" or deck is wider on the 5.4 and uses an all plastic intake (4.6 has an aluminum upper intake which can be adapted to fit on the 5.4)

I ended up getting the truck with a 4.6l to start off because it was the best deal I could find at the time. I was kind of disappointed when it came to pulling my trailer I wanted more power so I did the swap.

Hope that helps some with your decision.

 

i think they are both pretty good engines my dads 4.6 has 156,000 and no major problems but does like to miss...my uncle has the 5.4 with 145,000 on it and no problems whatsoever and has more power id say go with the 5.4 although either would prob treat you fine

 

Not sure where you are going with that, they (5.4L and 4.6L) use the same heads only real ddifference is the height of the block which makes the 5.4L a little wider so the intakes are different, other than that they are pretty much identical. No '97-'03 had 3V heads so that is moot.

 

I went so far as to pull my 4.6L out of my truck and dropped in a 5.4L. Well, I think having the 4.6 tranny and rear end along with the stronger motor makes it a little different than a standard 5.4 truck but I gotta say....that thing will jerk a knot in your rear when ya hit the gas. I got 35" (4x4) tires on it and it will turn them things over like nobody's business. If you can get the one with 5.4 in it to begin with, get it. It is a pain in the backside to do the ole swap-a-roo cause of the parts differences.

 

Both are good. Many swears that 4.6L are solid, so are 5.4L, sure there are couple issues but none are deal breakers. Both have similiar gas mileage, maybe just 1 or 2 mpg better on 4.6L. Trust me, you'll want the power of 5.4L. To be honest, when I first owned a 5.4L with 98, I was somewhat disappointed with the power. Reading this forum taught me alot. Learned to appreciate the 5.4L with the torque power I get pulling my trailer, and not to expect neck snap accelerations.