I don't know if it is the front driveline or the front axle but I get a constant clunk, clunk, clunk when in 4X4. It only happens when the wheels are turning faster then the truck is moving (i.e. sand). It won't do it when in 4X4 just going down the pavement. It just started after I played in a little mud. Everything is working as far as the 4X4 but the noise sounds really bad. I have looked at everything under the truck and it all looks fine and the front driveline feels solid. I noticed that my pinion angle has slightly shifted out of adjustment according to the marks on the eccentric cam bolts so I readjusted that but haven't tried the truck in sand in 4X4 yet. I doubt that was the problem though. Read my sig. to see how the truck is set up. Any help is appreciated. My dealer is quite a drive from here.

 

I took it out lastnight after adjusting those cam bolts and it is still doing it. I also checked the front shocks and they are tight. I guess I might have to live with it.

 

I have a 99 Ram. Sounds like one of your front axle ujoints is going out, will problably get gradually worse mine did until I finally couldn't take it and decided to fix it. If you are going to do it yourself it could apart easy or hard. My axle went the hard the way.