The only way to test ball joints is with the weight off the spindle, grab the tire and see if it moves back and forth (vertically). If it does, it's joint time. Same with tie rod ends. but horizontal wiggle. If you have OEM ball joints and they aren't gereasable (most aren't), they 'fill' them with a tiny amount of grease and they have plastic balls and are prone to wearing out, I replaced the ones on my F350 ford diesel long ago with Moog greaseable joints, did it myself. Not too had, just a lot off bull work.
Far as shocks go, the only sure fire way to tell if they are shot (if they arnen't leaking is pull one. The old bounce the corner of the vehicle (car) and see if it bounces more than once to determine if a shock is shot, don't work well with a truck because the truck is more heavily sprung. I'd pull a front, they aren't hard to take off and see by compressing and extending the shock (and listening to it) to tell if the internal dampening is gone or not. The shock should progressively resist compression but be easier to extend.
One thing I learned about shocks is, you don't want a gas charged shock on a truck, you want oil filled shocks instead. Gas shocks have a starting load and the equates into an ever harder ride because the 'shock' of the bump has to overcome the start load before the shock moves.
I just replaced my Rancho's on my truck (2nd set) with Skyjacker Black Max oil filled. You can buy factory direct from Skyjacker, saving you the middleman matkup.
Hope that helps you....