mine does the same and there is so many possibilties on the cause. could be calipers sticking, could be transmissions issues, could be play in u joint, could be play in the rear end, theres tons of possibilities. after looking around on my truck alittle, i did find that my spare tire had alittle wobble room. after tightening it up, theres much less noise, but theres still some there.
i asked a friend who is a toyota technician about it one day. he told me thats one of the most common complaints about big heavy v8 rwd trucks with auto trans. he said when it comes to a stop theres still pressure on everything, is bound up, then when u left off the brakes, everything settles back into place. and this seems to make sense bc he told me to pay attention to how loud the noise is in comparison with how hard you brake. if you come to a very slow gentle stop, it doesnt buckle or pops. but if you catch a yellow light and slam the brakes, the sound is way louder