engine/trans noise

This truck has a 6.0 engine with 56000 miles. When idling it makes a metallic tapping sound almost like a bolt hitting a shield. Sometimes the noise stops and other times it gets louder. I just recently serviced it and the noise is still there. If I rev it up just a bit it goes away. I have checked and wiggled every shield under the truck and it seems to be coming from the bell housing area. What have I missed?
Thanks
Mike

Loose convertor bolts? Cat internally seperated?

I'm thinking converter also..

I was hoping for something easier and simpler.... oh well

Thank you

Mike

I'm having the same problem.

Sounds like rattling metal?? Mine seems to be a harmonic of some kind when the engine hits a certain rpm level while in gear.
Wondered if it was a vibrating brake line or something.

Just had trans completely rebuilt and it had no effect on the noise at all.

If its an automatic check the torque conveter bolts that connect to the flex plate (flywheel). I had one back out once a long time ago and it was an eazy fix. I dropped the lower bell housing cover and had a freind turn the motor with a socket and breaker bar to get each one. 15 min job. A long shot but its woth a look if you can't find anything else.

If its an automatic check the torque conveter bolts that connect to the flex plate (flywheel). I had one back out once a long time ago and it was an eazy fix. I dropped the lower bell housing cover and had a freind turn the motor with a socket and breaker bar to get each one. 15 min job. A long shot but its woth a look if you can't find anything else.

I thought so too and would still if I had not had to have the tranny completely rebuilt a month or so ago with no change whatsoever. :popcorn:

If the sound is more like a tapping than a rattling, I had a similar noise from my '98, sounded like a lifter tap, seemed that way because it would get faster with the rpm. After days of crawling/listening around my engine compartment and re-adjusting my rocker arms, turned out to be a small exhaust leak, that i couldn't feel. Weird how the way something sounds can lead you in the completely opposite direction:banghead:. The sound went away after i torqued all the exhaust bolts down, it's worth a try. Hope this helps.