4L60E rattle... any ideas?

i've got a 94 K1500, 350, 4L60E i'm having a fairly intermittant rattling sound, obviously it's tough to describe over the net, but if i had to compare it to something, i'd
say it's like rolling small nuts (hardware... not the food) in a metal dish.
it only makes the sound in the moving gears, not park or neutral, and only lasts until i give it gas while in gear. (ex. sitting in park, no noise... shift into reverse, i get noise... shift into neutral, noise goes away... shift into drive, noise comes back... idle forward, noise stays... give it gas, noise goes away, doesn't come back) this only starts happening after sitting in park with the engine running for longer than say.. 10 minutes, and not very often, maybe once a month
any help would be greatly appreciated, everyone i've talked to so far is pretty clueless
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Just a guess, but do you have those thin metal exhaust system heat shields? A real annoying tinny-like noise when they rattle
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snipped-for-privacy@webtv.net (ken) wrote in message

if you're talking about the ones that wrap around the exhaust manifolds, no i don't... my headers don't leave enough room for them. similar sound though, the one i'm trying to describe is a bit heavier.
dan
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From the age of your vehicle, it is possible that the sound is from your cat converter. My 94 Sub 1500 had a similar rattle that I traced to the cat. It would rattle a little at first acceleration.
My 2 cents,
Rick

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