Ok, so I installed the 6" shackles today, and everything fit in fine, boosting me from a 35.25" height to a 36.75" height in the rear suspension. However, when I went to crank the front end I had some issues. I pre-measured, the front end and was at about 34.5." I lifted the front end with my floorjack, and turned the adjuster bolt 10 times. It looked perfect,but my upper control arm was sitting on top of the bump stop. By the time I backed it off, to the point where I have about 3/8" clearance between the uca and bumpstop, I am sitting at 34 3/4" in the front. I'm scratching my head here, trying to figure out what to do. Little help?

I also read that you can re-index your torsion bars, but from what I've read, I don't have nearly the expertise for that. Assuming that I could figure out how to re-index the t-bars, would that resolve my issue?

Oh yeah, its an '03 4x4.

Reindexing is only for when you run out of adjustable length on the adjusters... Sounds like someone may have cranked your torsion bars up a little in the past already...

That's the thing, I bought the truck used in '06, but as long as I have owned it, I have never seen signs of prior wrenching by anyone else. And if somebody had already cranked it, wouldn't it have been above stock height?

I think I am just going to take it off tomorrow, unless anyone has any ideas?

Without looking I can't say for sure.
I've successfully done an Xterra and a frontier. Then on another frontier, I had the same problem as you and his front could not go as high to even his out (well to achieve that 1" front to back height difference). He's stuck with a little more rake unless he has some payload in the back. Do you know if your rear springs are stock or maybe you have an added leaf for towing/load?

I have pretty much the same problem. I just figured it was because I drove around with half a PML for so long (t-bar crank, stock shackles... gets rid of the rake) I got some new bump stops to help... I guess they were worth the $10?

Here are a whole bunch to choose from.

I believe I have the 99102's? But you could go for the 99132's if you REALLY want low pros.

The stock torsion bars could be wore out too. Might not hurt to buy new ones and try it again. 4x4parts has them for 180.00