most likely the shocks are gone. You can do a quick visual check to see if they are oil soaked. only other way is to take them off and see how it reacts when you push down on the shaft.
other than that I would do a quick check of the other items I showed you especailly if truck has been drivin in snow. upper and lower a arm bushings might be shot which I have been seeing or balljoints worn or tie rods loose.
If you can lift the truck up and hold tire and 3 and 9 position and rock back and fourth and then at the 12 and 6 position and do the same and you see movement means balljoints have play and should be changed
then you can pull and push on tie rods to see if there is movement in the ball joint area and if so should replace it.