A truck's suspension (springs and shock absorbers) is much stiffer than a car's. Small bumps in the road, which are absorbed by a car's suspension, are transmitted to a truck's driver.
If its a motor knock it will do that while sitting/reving engine not just driving. If it's only while driving try different things to check it out. Does it do it over bumps?(parking lot speed bumps are a good test track) Maybe only when cornering? Try pushing up & down on the truck while its sitting and see if it does it. Does it shake also?
you can through out the camber and that causes your tires to wear on one side or the other and it can also do damage to you idler arm and tie rods, which is an important part of your front suspension
suspension.
Worn, loose, or broken suspension parts. Have the suspension inspected by a professional. This can be a very dangerous situation, and I suggest you attend to this ASAP.
Bumps in the road.
Sounds like the shock bushings are worn out are loose.
Worn suspension parts - struts Loose strut mount?
It maybe your suspension that squeaks when ever you go over the speed bumps.
It sounds like it has whats called bump steer. You need to have the camber of the front wheels checked by steering specialist.
It might be the CV joints. Go to a front suspension specialist and have it checked out.
When was the last time you had the suspension lubed? Did someone swap in some urethane bushings? They tend to squeak .