2001 S40 Bangs

we have a 2001 Volvo S40 1.9T with 104k 5 speed automatic..

I noticed that whenever you drive this car say in town around 25mph and you let off the gas and step on it again the car Bangs quite cloudly and it shakes the car.. its almost like dropping it into drive from a dead stop while pushing the gas pedal..

if you do it at 60 it still does it only not as bad.. but its still there..its hard now to not to get it to clunk when your in town.. if oyu slow down for a red light and it turns green adn you gently pushed down on the gas it Clunks very loudy and the car shudders..

Anyone have Any Idea whats wrong?

I have no idea what kind of tranny these cars have and how they work..

I had this problem with one of my cars. It was the front breaks and the car needed an alignment. Hope this helps to get some sort of idea.