2002 GMC Sonoma noises from left front wheel

My truck has a bad groaning, sound when I drive over any uneven surface. The sound comes from the area of the torsion bar suspension in the left front wheel area. The sound is constant as long as the truck is going over up and down movements. Since I know nothing about torsion bars, any help will be welcomed. I am afraid that the wheel is going to come off on me.