The TTB system pertains to both the drive-train and the suspension. TTB is the 4x4 version of twin I-Beam. One of the two 'beams' actually contains the differential. That beam has a partially enclosed drive axle, very solid-axle like. The passenger side is driven by an exposed drive axle. Both sides have U-joints. There are no CV's like there are on the newer IFS trucks.

IFS on the other hand can be sprung by either t-bar or coil springs.

 

so i take it i need the 4" lift then? if that ill be getting 35" then

 

You don't need a 4" lift.... just put the 3" bl on and you can run 33"s with out a problem.
edit. You already have the 3" body lift. Put those darn 33"s on already!

 

yeah i put a set on b4 and they rub the lower part of my front bumper. have to hack some off for them to work. I did know "if I had" which i dont, cracking up toursion bars would work. I might do it anyway

 

were u using stock wheels or wheels with stock off-set/backspacing?

 

33" pro comp all t's on a 15x8 Streetlock
Series 152 rock crawling rims.

 

33x12.5 fit everyones truck with just the 3 in body lift tons of people here have that setup. no reason they shouldnt on yours, ecspecially since you got the extra 2 in.

 

yeah i put a set on b4 and they rub the lower part of my front bumper. have to hack some off for them to work.

 

ok sigh first i will make this easy for you YOU DONT HAVE TORSION BARS AT ALL JUST FORGET THE WHOLE CONCEPT


ok with that out of the way if you need to trim on what i am guessing is the plastic valance not bumper just take a sharp utility blade and trim its easy

 

Love the numbering system neil!