Bumpety Bump in the front End...help!

[chargedstang89]

On the way home from work yesterday, I slowed down to about 5mph because of traffic and from the front, right side of my truck, there was a loud BUMP BUMP BUMP and my hood was shaking. I thought I had a flat or ran over something, so I pulled over, but my tires were okay, and everything under my truck looked normal. I have an '85 GMC 1/2 ton 4x4 with 3.5" body lift. I got back in and proceeded to drive, and all was well. However, when I rolled the window down, I heard a constant ticking or grinding sound, similar to that of something rubbing on the rim or a gritty bearing. I put the tranny in neutral and it was still doing it, coming from the front right side. When I got off the highway by my exit and stopped, the truck made that loud bang sound again and I felt a jolt in the truck, and then that grinding sound went away and it hasn't done it since. What in the world is going on? Are my hubs going bad? No, I did not have the truck in 4x4. It has a 700r4 tranny and the 208 transfer case (gear driven). I believe it's the 208..lol Anyone got any input????