Motor mount/tranny mount....Never heard that kind of bang from throw out. Throw out usually sounds like a rattle can or bad radio station. Could be Ujoint also, I don't know the closed driveshaft system though. AD people will respond. A bad mount will hop more in lower gears due to torque load/gear ratio. Need to fix ASAP and not drive, can do some big damage. Are you sure it's from front area not rear end? A busted gear somewhere will sure bang! Tranny or rear. Settling down as shifting higher, leads me back to mounts or joints. 1st and Rev is a slight hint to a problem in tranny but they are both high load also. Let's see what the other folks have to say.

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