It's a repeated clunk clunk clunk. It does do it over bumps but it doesn't seem as loud as when turning. I just drove my girlfriend to work and I also noticed that when I let off the gas a bit and let the engine slow down the car it also does it. Also seems like even if there are no bumps it'll still clunk but a lot quieter.
Also I was wondering if you happen to know about the transmission or clutch too?
In gears 1-3 no matter how slowly I release the clutch, there's a slight thud as it goes into gear or as the clutch engages. Could it possibly be because the manual transmission fluid needs to be changed?