Most Techs do NOT know how to Align these IRS suspensions. They'll claim they do and did it right but they won't get it right. I just went through this mess again after installing the ProComp Lift and I'll share so you'll have an idea of how bad it is.
I went to a local tire shop that I've had good experience with before and was highly recommended by the Offroad store. They had it for 1/2 a day and said it was done but it didn't feel right. So I took it back and let them have it for an entire day and told them I want the print out. When I picked it up, I had the printout for the front only and not the rear and the rear still didn't feel right. I was going to take it back and decided to request a refund instead so they were happy to oblidge and refund my money because they preferred not to hassle with it again.
So, I took it down Saturday to the Nissan Dealership who fixed me up last time. It was a different tech this time and he said he couldn't get the wheel sensors on so he refused to do it. So, I went to a Cadillac Dealership who's supposed to have one of the best techs around. Well, he was off on Saturday and the S/A confided in me and said "look, the tech you had at the Nissan dealer is good but he usually only puts in 1/2 effort at best. The guy I have here today will give 100% but he's not familiar with an IRS and will likely blotch it up."... So, he told me of a place that's the best around at aligning lifted trucks.
So, I went to this other place and they claimed to have the best alignment techs in the state. I told the guy I've heard that one before so we'll see but to also let me know if they have any problems because I can likely get in there and tell the Tech where to crank. Well, that kid had it perfect within 20-mins and handed me the printout and told me if it's not right just bring it back and they'll readjust for free (as they should).
The prinout confirmed my suspicion. The rear end Toe was still so sickening far out of wack after the last place was done and that's why I didn't get a printout for the rear. The final prinout after this tech was done is all within 1/64" to spec at the worst measurement. The ride is now perfect and the stance looks great.
Point being, it's not the machine, it's the Tech and there are VERY few techs who are qualified enough to align the rear end on the Armada regardless of what they say.
Make sure you gat a Printout and make sure that it's YOUR printout that they hand you with all 4-wheels spec'd. The guys who can't get it right, rarely admit it and will do whatever it takes to hide their mistakes.