JHanson,
After adding new, somewhat softer, 2" over stock Deaver leaf springs to my tuck front and rear I found that with the camper on the truck it led to unsafe roll in turns which caused oversteer in a turn at speeds over about 45 mph which then led to sway (or oversteer left and right - nose dives into turn and rear end tries to come around) from trying to correct with steering input. At highway speed it led on one occasion to a back and forth roll and oversteering correction until I bled off speed - frightening.
I took the truck back to Deaver and Jeff added another leaf to the rear springs and stiffened things up a bit. That made the situation much better, He said if that didn't solve the roll issue that I I should add an anti-sway bar (anti-roll bar).
After the leaf addition the truck was still rolling too much in turns for my comfort so I added an ADDCO stabilizer bar (anti-roll bar) to the rear. I would have preferred Hellweg but they no longer make one for my old truck. The rolling is no longer a problem but that left me with an annoying wander in the steering that was not as noticeable previously.
I had previously replaced all the tie rod ends and had the bearings and front u-joints serviced which left only the steering box as a potential suspect. I evaluated the steering box and found that it had too much play so after reading a lot of reviews about problems with Redhead steering boxes I replaced it with a Bluetop steering box. It still has more play than the original steering box had when new and well into its life, indeed the truck handled like it ran on rails until it had over 325,000 miles on it, but the Bluetop unit is within the spec limits so not returnable.
Bottom line; Adding lifted height springs coupled with changing the spring stiffness can lead to unintended consequences. The roll and resulting sway are gone but I still have a little bit of steering play which leads to a small amount of wander within a lane width, particularly on uneven pavement. It is annoying but not particularly unsafe in my opinion.
Shocks are new Bilstein 51xx series all around.
