Originally Posted by mrolgren

Take a look at this and see if it helps out.

https://www.f150online.com/forums/ot...e-pulleys.html

Also just search for "Underdrive Pulleys" and you get a bunch of threads on this topic as well as the e-fans.

Good Luck!!!

Originally Posted by Roadie

Goto this site and punch in your VIN# and it will tell you your hp among other things. I've seen several different ratings for 05's and newer 5.4 engines.

https://www.fleet.ford.com/maintenan...ls/default.asp

Originally Posted by Tylus

all 5.4 3v's from 2004-2008 in the F-150 are rated at 300 bHP

there is no other HP/TQ available in them.



the reason that site quotes different numbers is because of the Expedition. in 2005 Ford offered 2 different 5.4's for the Expy. The 2v and the 3v.

The Fleet Ford Website thinks that the F-150 is the same way.

Originally Posted by 4.6 Punisher

Compared to Mopar trannies, these are bullet proof.

Originally Posted by Tylus

I would

4x4 trucks lose more HP than a 4x2 truck via the t-case (roughly 15 HP)...and the drivetrain on a 04-08 F-150 sucks up HP without good tuning

custom tuning will place a N/I Roushcharger @ about 330 RWHP. the Roush tuning sucks...it leaves HP all over the table that any 1/2 decent tuner can recoup safely



FYI, there are many 400+ RWHP trucks on this site with the stock tranny and zero issues. I drove my FX4 like an idiot up to the day I sold her and the tranny was solid...not bad for a 6,000 lb truck that could powerslide pretty much on command. and mine only had the 412 crank HP roushcharger



edit:

sorry, but I have to disagree on this. these are hardly weak trannies. prior to buying my RoushCharger, the tranny was scaring the crap out of me. I finally called up Roush with a list of questions.

1 of the questions was specifically aimed at how strong the tranny is. The guys at Roush apparently did some drivetrain testing back in 2004/2005 and they rate the 04-08 F-150 drivetrain as capable of handling 500 WHEEL HP. That is anywhere from 550-600 crank HP. this is why Roush offers to replace the 3yr/36k warranty when you install their blowers on a new truck

Couple that with the # of guys who've been running blowers since 2004 with zero issues...and the way I drove the truck....I would say these trannies are pretty damn stout.


I know there has been a plethora of "broke tranny" stories recently, but then again, these trucks have been on the road for 5 years now. Also, Ford made millions of them. It's all about percentages. Sh*t happens guys. I'm sorry for those it happens to though

Originally Posted by DarrenWS6

Just before you think of supercharging, realize these transmissions aren't made of platinum either, beef the engine up, beef the trans up, because its a good possibility of failure. Not the general modifications, but supercharging and using the supercharger to its full potential can kill these weak transmissions.

Originally Posted by FX4 Matt

If you beat the **** out of your truck you will fu*k it up. I have almost 90K and I have not had one trans problem. and there is plenty of guys that have supercharged trucks with no trans problems