A little background info before my question. I have a 99 f250sd 4x4 with the 5.4 two valve ( I think they were all 2 valve in trucks that year) with a 5 speed manual zf tranny. I have about 260k miles on everything. I use the truck for work and play. I don't care if it is fast, I do want more torque for towing and 4 wheeling. The engine siezed and the tranny needs attention. My question(s) are what should I pay extra attention to during the rebuild. I hate doing things twice. And what kind of parts should I get to get more torque ( not monster truck level, but towing in the mountains of Colorado) ?

 

best thing for "power improvement/ torque"... for towing is gears in the punkins...depending on what, or how much tonage you tow & how often will help determine the ratio for you.

off hand... because your 3/4T & gonna be guessing that you have at least 5-8000 lbs behind you.....given that WAG , you'll prolly be happier with 4:56 or 4:88 especially in the mountains. Then make sure to use a heavy duty clutch.

now the engine would benefit from long tube headers and a tuner, as long as you're getting a different engine

these things don't come cheep so be prepared to lighten your wallet

 

Im not planning on getting a new engine, and I was more wondering if there was anything I could do to the engine (and trans) internally, as long as I am in here. And for an update it appears a timing chain runner broke (fragmented), a piece jammed in the timing gears, some went in the sump and cloged the oil pickup, to deplete the engine of oil. I think I caught it in time to alleviate extreme fatal damage.

 

With those kind of miles you would far better to completely rebuild it. Or find a lower miled running engine from a 04' heritage and swap it in. Not necessarily focus in one or 2 things and stick it back together... with (fragmented) pieces of timing chain tensioner /guide...those little bits can get places you don't want or realize and show up and cause you to do things ALL over again.

none the less;
I would make sure to put PI (performance improved) heads and new oil pump and injectors. maybe regrind or get a cams that is designed for for power in the low to mid RPM range ( no sense in getting cams that is going to make all the power above you are normally going to operate RPM wise). Shucks... if real power is what you want then super charge it. depending on the $$ funds available.

I'll stick with the original suggestions on tranny and gears

 

Heres an update; the #3 and #7 rod bearings were seized to the crank, the rest of the rod bearings showed signs of lack of oil. I kinda expected this though.

I am going to do a entire rebuild on the engine, and have the heads gone through (I was starting to hear valve lash on a cylinder). Might as well do it while I am this far.

As far as the supercharger goes..... I have 2 turbos from a chevy diesel sitting in my garage doing nothing but taking up room. If I do want to go that route, I am obviously going to have to change pistons and lower my compression. My next question would be if the aluminum heads be able to handle the extra boost? I don't want to sound like I am married to the idea, but if I was to do the necessary engine "upgrades", would a turbo actually get me what I want out of the truck? or is it a step in the wrong direction.

I guess I should also mention the other things I am planning on doing to the truck during this down time;
1- re-Balance the drive shafts and get the double cardine u-joints replaced.
2- Duel exhaust. (the existing exhaust is about to fall off anyway)
3- Add a second battery.
4- Front bumper with a removable winch (on a receiver)
5- Tranny rebuild (syncros in specific)
6- re-seal my transfer case. (looks like there might be a leak)
7- replace the ignition coils/components with aftermarket.

 

sounds like a serious plan
you can use the turbos if you like... but... considering ford already offers a supercharged version... my instinct is to go the supercharger (SC) route. a whole lot less lag involved and still very much a daily driver. and the ECM is readily available and a whole lot less plumbing involved

that said I'm sure if you still want to use the turbos...then the crankshaft would be best if it was forged steel unit just like the ones that are in the SC units...as far as the heads go I'm pretty sure the SC units are alum. & I'm sure that there a many that are running turbos

or swapp in a diesel...that would get you the grunt that you are looking for

get on You tube... some of these guys are running some pretty serious boost with either SC or turbos