Not 3.5". Even if they are Pro4x coils maybe 2". Since the truck's an '08, it didn't come with cam bolts, so the camber being off would explain it, and even Toe can cause this.
madrock, did you get it aligned? Did you buy cam bolts?
After giving it a little thought (hopefully I have it correct), I can see a 2wd getting 5". The 08 4x4 springs level an older 4x4 at 2" (1" due to a longer spring and 1" due to a stiffer spring). A stock 4x4 sits about an inch higher than a 2wd truck. So the 08 4x4 springs will lift a 2wd truck roughly 3" without taking into account the weight of the truck. Now, knowing that a 4x4 is a few hundred pounds heavier than 2wd (and all that weight is mostly in the front) then an extra 1" with the 5100's on the lowest setting seems pretty reasonable on a 2wd. So we're at 4" now. So 5" at the middle setting seems like it is possible. I don't know what will happen with the coil bucket contact situation with 5" of lift. Hopefully I didn't miss anything and have the numbers correct NorCal (I know you know your stuff).
We also can't forget that tires come into play since we're measuring ground to fender height. So if the tires were changed at any point between the before and after measurements, that will increase (or decrease) the amount of "lift" too. We should really be measuring center of hub to fender to take out the tire contribution.
At any rate, with this much lift, the 08 4x4 springs on a 2wd will be a hot ticket item for sure.