And it's a safe bet that an '02 non Harley/Lightning/7700 truck has the 4R70w anyway.

Count the pan bolts or tranny code on the door jam sticker. U for 70, E for 100.

Adrianspeeder

 

i just was doing some serchin on the net and stubbled across this i have just switched from a 4R70W to a 4R100 trans and it was kinda a pain getting all the parts straightned out my truck is a 4x4 and the only thing i still don't have is the torsion bars my local dealer tells me u need the spring code from a truck that has the correct ones to order them i was wandering if anyone had the code, part numbers, or would know where i could get a set of the your help would be aprieciated as i just repainted the truck and used only a quarter tank of gas then blew the trans its been sittin for awile

 

i dont see why ya just had your 4r70w built up. Money behind yeah, but power capability ahead.

 

im doing a swap and the 4.6 was origionally in the 99, the one i bought was from a 2002 fx4, does that matter?

 

part numbers: F75Z5B326KB and F75Z5B327KB Spring Code Seven. These are the part numbers for the longer torsion bars you need for the crossmember to clear the transfer case. BadAndy, what is your email? I would like to discuss the swap with you.

 

most likely the truck your "new" engine came from also has a 4r70.

you can add a shift kit to the 4r70 to help it out a bit and with a "stock" 5.4 you'll be fine.

I'm running a supercharger on my 4r70 and it only has a valve body upgrade in it it's close to 100k and still works fine (even though it's days are numbered and I know it)

turbof150.com shows a turbo 5.4 that puts 966 rear wheel hp thru a 4r70 transmission (a monsterbox)

 

trust me i have way more power than a 4R70w will handle i got 487hp and 512lbft to the ground out of a performance built trans from phoenix but they always slipped and i blew out 3 of them in the last 3,300 miles

 

look into the 4r75 swap from darrin burch, that's what I'm going to end up doing

 

the 75 has another gear but the holding power is in the clutch pack ive been doing alot of research because transmissions arn't cheap to buy all the time, the 70 is only capable of 3 clutch packs the 4R100 is made for power and torque thats why they put it in the superduty trucks... with seven clutch packs and good converter the deisle drag guys are put numbers though these things they are well proven i had a guy from pheonix retrans tell me they could build a 4R70W for my truck i bought it and after replacing 3 of them and paying shipping back and forth being stuck with out one while i waited for them to fix it i can tell u that the $2,600 intial cost plus shipping and (installation and removal fees if you don't do it yourself) was the single worst mistake i've made in my life

 

the 4r75 only has 4 forward gears...

but enjoy your swap, I wish you good luck

 

ok i looked into it rated torque on a 4R70w is 700blft a 4R75 is rated at 750blft and the tourque converter runs 2:1 wich means at best there is 375lbft only 25blft more holding capacity than a 4R70w if thats enough for u than great. i just want u to be aware what can happen because it cost me alot of cash and i wish the guy who sold me that trans would have said it wouldn't work when i gave him my numbers. My swap to a 4R100 is proving rather costly and a lot of hunting around for the correct part numbers but i got it all in i just hope with a little better information this time around everthing works.

 

Did you get your correct torsion bars?

 

Both the 4R70W and 4T75E are four speed transmissions. The first number on the trans name is the number of gears.