hard thumps are usually due to
bad strut dampers
saggy springs
bad control arm bushings
bad strut hats
bad ball joints
if you get your car oiled from underneath, your bushings are shot, If you ever had any work done and the lower arm bushings were tightened whilst the wheel was free hanging in the air - your bushings are shot now - they need to be tightened with the wheel in normal drive position only. The factory manual heavily instructs this - and they recommend to use a jack under the hub so the car lifts onto the jack then tighten everything.