My 98 F150 4x4 is unstoppable; 4.6L with 5 Speed standard tranny. I have 218k miles on it, and just recently replaced the original battery. That pretty much sums the entire truck. Other then standard maintenance and tires I have not had to put over $1000 in repairs in all those years. The one draw back is that I haul a 20ft trailer which sometime is loaded with 6-8 thousand LBS of lumber; I obviously have uped the spring package. Its just too much for that 4.6L engine when going up hills though. I have a second '98 4.6L I would like to turn into a 5.4L. From my understanding the 5.4 has the same cylinders as the 4.6L but has a longer stroke. Could anybody out there provide me with the list of parts I need to make this change. Not against putting in high perf parts either, if it boosts torque and HP. Off the top of my head I will need to replace the Crankshaft, Rods and Cams, but have no clue which crank or cam to use. Been a long time since I have rebuilt an engine (not counting the Harley) and I have no clue whats out there.

Would appreciate any help from you all.
Thanks!

 

the 5 speed trans cant handle the power of the 5.4 stay with a 4.6 or swap to a auto trans.

 

Pretty truck STR8T SIX. I do have another '98 F150 sitting out back with an auto tranny in it. It actually where I was getting the motor. I was going to put the 4.6L I removed from the first truck back into it. My reasoning was that the standard tranny would be stronger than the auto. Guess thats my old mind at work. I would still like to do the rebuild, I will just leave the 1st truck as is, and do the rebuild in the truck with the auto tranny. I have alterior motives for doing this rebuild. I have a 14 year old nephew who is in trouble a lot so I am going to take him in. I am hoping that I can get him interested in things other than hanging out with idiots, by getting him interested in trucks. What 14 year old doesn't dream about rebuilding a truck that he can call his own someday?

 

I agree with six, the 5 speed won't hold up. Stick with the auto.. I don't have much advise on building an NA 5.4L from a 4.6L block...? I honestly would just look for a low mileage engine from 99 and up and spend the rest of the money on upgrades like long tube headers and exhaust, custom tune etc... It would be twice the truck your driving now.

Yea, get the kid in the garage. That is a perfect age to start learning mechanics. If the job drags on too long though, he may loose interest. You couldnt keep me out of the garage when I was that age. I was already modifying riding lawnmowers, dirt bikes etc.. Loved it. And kept me out of trouble... for the most part.

 

#1 get yourself some research, it's FREE (for example the 4.6 to 5.4 swap "how to" thread on here)


#2 the n/a PI 5.4 and 4.6 two valve motors use the same pistons, same heads, same cams and a bunch of other parts...

#3 the largest displacement I've seen a 4.6 go to is a 5.3 (with a serious overbore) and not very budget friendly...

#4 what are your goals for the truck? how do currently / intend to use it

#5 have you considered a ZF transmission swap to replace that mazda POS 5 speed your truck has in it now???

 

You are already killing your tranny - max tow rating with the M5OD is around 3000#.

What you need is a PI 5.4 along with an automatic or a ZF manual conversion.

 

It'd be cheaper and more practical to just swap in a PI 5.4 with the 4R75 auto in behind it. You can also do some performance mods to the 5.4 to help it out even more with what you'll be throwing at it.

 

OK; You guys talked me into it. As much as would like yto do a total rebuild I will save that for another time and pick up a refurbed 99 5.4L and do the swap. One last request for help though. I have tube headers on my current truck. Other than headers and exhaust what bolt-ons are out there to help impove Torque and HP? Thanks!!!

 

True duals, gotts intake, dyno tune. Could regear the rearend for better towing.

 

Need to pick up and after market computer for the Dyno; correct?

 

shouldn't... id find a zf5 and a 5.4 and build the 5.4 up!

 

No, the tuner will use a programmer to tune the stock computer.