Drive Shaft question?

[Fergy19]

Hi, I've recently had some issues when switching into 4x4 in my truck.. As soon as its locked in and I drive forward/reverse there is a loud clunking sound coming from what I suspect is my driveshaft? I've crawled under the truck (not very hard to do lol) and wiggled the front driveshaft around and it does seem pretty loose but I'm not entirely sure. Any other suggestions?

 

[nswsparky]

check the caps of the u-joints I had one spit. There are 3 u-joints in the front dirveshaft.

 

[Stroked68]

Could be the joints on each end of yer front axle. No matter what u join it is, get good ones like moog or some other brand that has grease zerks. I hate non greaseable joints!

 

[f100cleveland]

Did you get longer drive shafts with the lift? You might be over extended on your slip joint and its barely engaged and splines are worn.