Alright I thought it was coming from my tranny but after further investigation it sounds like it is coming from inside the oil pan. It does the clanking noise mainly when you rev the engine, so push the gas pedal fast. Any suggestions on what it could be?

Is it a continuous knock? does it only knock once? twice?

It clanks when I rev it up and a lite tapping sparatically. Also when I drive it it does the tapping/clanking until it shifts.

Check for loose torque convertor bolts and or a cracked flexplate. A cracked flexplate will start as a light ticking sound and progress into a severe knock. It will sound like it is coming from the engines bottom end.

Just a suggestion but make sure the dipstick didn't break and is wrapped around the crankshaft, this happened to a friend and it drove him nuts until he figured it out...Tj