When going high speeds and hit a bump the truck has a tendincy to jerk at the wheel what do u think that is?

Your vehicle isn't equipped with struts. It uses shock absorbers.
You should have the suspension thoroughly inspected for worn components: tie rod ends, ball joints, bushings, etc. They should also inspect for worn hub bearings.

Rich is right; have the front suspension components checked out first.

Of course, it could also be the story that my sister gave us. She insisted something was wrong with her Mountaineer because she said it "went out of control" when she hit a bump, yet everything was tight and still is now, 40k+ later... after multiple inspections, we came to the conclusion that it was the driver :)