Quick vibrating noise comming from transmission/??

[toki]

Ok, the way I think I can best some up the sound is if a piece of heatshield were vibrating againt the firewall very steadily...kind of that thin metal hitting thin metal sound, but it is comming from the stereo/AC/shifter area to me, and you can only hear it while in gears 2, 3, and 5 and under throttle...it's pretty quiet, not loud by any means. 4th doesn't really do it all, which is wierd becuase with trannys 2 3 and 4 are usually the ones that go, but it seems to be the worst in 5th actually. I am thinking it's the transmission, but I really don't know. Any ideas? It's like a very steady CSHHHHHH if that helps at all. I know describing a sound isn't going to do much..but you know. Any guesses?

[Scott McLellan]

Hey you asked for ideas. In order:1. Universal joint going out.2. Driveshaft out of balance. Possibly debris or incorrect mounting(If it has been removed was it reinstalled in the exact same position like bolt holes)?3. Have you checked the transmission fluid at all? 4. Engine needs tune-up.

[deviousKA]

its probably one of your heatsheilds on the exhaust. kinda like you first suspected. does it seem to go away with different rpms in the gears you mentioned?

[toki]

it is the most noticable in 5th. i can be coasting at ~2200 rpm, be totally quiet, give it that little resting the foot on the gas 7~12% throttle and it will start up immediatly.

[Scott McLellan]

Sounds more like a universal joint to me.