Noise on acceleration

Hi, got some strange sound coming from the car on acceleration. Brought the car to the dealers, could not confirm where the sound is coming from. Sound only comes on when accelerating from low engine speed. Around 2000-2500 rpm. Personally sspect its the torque converter. But cannot be sure anyway I can check to confirm if its the torque converter?? Sound does not come on on idle.

[jeffsr]

What does the ?sound? sound like??

------------------
Jeff Lawrence
1989 300e
2000 Dodge Grand Caravan SE

Its an intermittent sound. Initially, it sounded like the exhaust was leaking. However, upon further observation, it seems like its coming from the TC. I'm not sure if I'm giving the right description, but it sounds like a pumping sound(like, tat-tat-tat, high frequency of pumping). Definitely NOT rattling, like metal on metal. Sound comes initially with a soft hissing sound, very slight. Then after that comes the pumping sound. Happens only within a specific engine speed range and only when pickup from low speed. Went to an independent workshop, they did not know where the sound came from. Went to the dealers, they too could not detemine the cause of the sound. The only reply was that the sound is not very obvious to them. But its damn obvious to me. Danm frustrated about this,been having this problem for 3 years. Could anyone out there at least describe to me the possible noises generated by the TC??? Really desperate.....any help appreciated.Thanks.

[stevebfl]

Torque convertors do not usually make noises in MBs. Sometimes vibrations and sometimes flexplate noises. The flex plate noises are usually worse at idle.

Its so hard to relay the concept of noise as all noise is some sort of vibration. My first feeling is you have a load related mounting problem or universal/Cv joint problem.

My advise is to take it back to someone with experience and have it evaluated. You should try and drive with the technician and be sure they are aware of the level you are seeing. One of the hardest jobs is to isolate noises. I have driven many cars with multiple noises; some appropriate, some not, but only one bothering the customer.

Steve, thanks for your reply, could you please elaborate on the "load related mounting problem or universal/Cv joint problem"? To me, personally, the sound does not really sound like a form of vibration at all. It sounds more like slipping, the first thing that came to my mine was the fan belt. After having checked it, I discovered that it was not loose. So I came to the conclusion that it could be the TC. Thanks, any help is greatly appreciated.