well, if you built up the rear end or swapped to a 9.75, built up the tranny, and modded a supercharger to fit it, it would work great!

 

I say work with what you got first and then if it brakes upgrade. if your really worried about your rear end being to small step up your ring and pinion to something stronger. Anything is posible if you have money. check out www.weinlemotorsports.com they do custom sheet metal intakes for any car or truck you would have to give him your intake for all his measurments and stuff but im sure he could fab you up a supercharger manifold for a Eaton M90 or M112 that you would have to supply of coarse. you can get them fairly cheap on ebay and they are fully rebuildable so you dont gotta worry about not finding parts. Ive worked with Mike at weinle motorsports personally for my Allen supercharger. i had him cut and re weld the manifold from a 5.4L to fit my 4.6L.

 

With the release of the "new" F150 in 04, they also released a new, heavier duty trans for the 5.4. Now the 4.6 gets the old 4R70W and the 5.4 3valve gets the newer 4R75W. I think they then switched to the 4R75E, but am unsure when and where on that one.

I agree with the first part. 100% Just be careful not to get into the "weak link chase". Where your upgrading all these different parts, chasing the weak links as it moves through the drivetrain.

I disagree with the last part, 100%.

Basically, to "strengthen" the ring and pinion, you need a higher gear ratio. a 3.55 ring and pinion teeth will be stronger then the 4.88, so you would have to give up gearing. Doing that will put a HUGE strain on your transmission. You could probably have someone make you a ring and pinion set-up from 4340 steel, or a chromoly set-up, but this will cost ya. Best bet would be to swap in the ford 9.75" rear. Its pretty much a straight swap. You would also want chromo axle shafts, and with all that modding, it would have been stronger, easier, and cheaper to swap in the larger axle.

You CAN upgrade the spider gears, or limited slip unit though. Run a detroit and no more bustin spidergears.

Just my 2 cents.

 

The only reason I thought that they were the same was on Vehix, both the 4.6 and 5.4 call for a 44Q and the 4.2 calls for a 44M for 2008, but if you look at the specs for a 2005 its a different trans code for each engine. I really don't know what the codes mean though.