Strange Popping only when WET!!

[CleanBauer]

I have a 99 Eddie Bauer Explorer AWD. For about the last couple of months when it is either wet or snowing. ONLY when it is wet or snowing. There is a persistent and extremely noticeable pop/jerk that occurs from what at first felt like the front passenger side and has seemingly shifted to the middle drivers side. It is hard to locate the exact place where it is coming from but it ONLY occurs upon braking from speeds around 30 mph or hard braking in general. There are brake noises (tings and pops) coming from what seems like all of the wheels when accelerating from stop (again only when wet) so this leads me to belief the popping is associated with the brakes in some way but I don't understand it. Given that it is 4w Disc, I don't feel any pulling or noticeable resistance from the back so I don't think the calipers are seized. There is NO noises or issues with the brakes when it is dry out, except MAYBE that they seem a little stiff. Any help would be appreciated!

 

[Turdle]

Hmm-
you might check the caliper bracket bolts on the inside of the spindle-they will work loose-

 

[mboh03]

I have a 98, this maybe far from the problem, but it could be the AWD mechanism. Mine will give this little jerk or pop as the transfer case is trying to decide to kick in or not when the roads are wet.

I may be far off but just food for thought.