Wow,
I am not trying to flame anyone here but the assumptions run rampant.

I just traded my '01 4x4 Screw w/IFS for my new '05. The '05 has coil overs while my '01 had torsion bars.

I got 2-2.5 inches of lift by cranking my '01's torsion bars. This did not affect the stability or alignment due to the Long-arm/Short-arm suspension. It was a great mod level the 4x4s. Just remember to to adjust each of the bolts (2) the same amount.

I never heard leveling kits for the 4x4 until the '04s came out.

 

Alignment should be covered under warranty for the first year by Ford.

A leveling kit (Daystar, Autospring, etc.) won’t void your warranty either.

 

this sucks. i took my truck in for vibration and they said it was my alignment. my front tires had some rubber taken off from rubbing up against the curb. they said because of this i had to pay for the alignment. ended up paying 180 to get rotated balance and aligned. sometimes i hate ford...