Please help I have a 02 Trailblazer making a loud thuding noise from underneath. I have changed both front and rear rotors and brake pads. I have also changed the front right calliber. Noise is still there anyone have any ideas??

When is the noise present? Is it over bumps, while braking, or while turning? The Trailblazers have a few things that go bump for various reasons, just need to know when it is doing it before we can be of much help.

The noise is all the time. the slower you drive the slower the noise. The faster you drive the faster the noise.

Almost impossible to diagnose noises from our desks, someone needs to road test this to actually hear the problem, wheel bearings are one possibility. A bad tire another. If it started after work was done, focus on that area.