Banging noise?????

[garywj]

I can hear a banging noise, similar to a rod knocking, but not as loud. I crawled under the truck, and it was definitely coming from the belhousing, or the front part of the trans. What could it be?

[Philip]

Check the crank shaft for end play. If you loose the thrust bearing it can allow the flywheel to touch the engine adapter plate.

Setup a dial indicator on the harmonic balencer. Take a srew driver and shove the crank forward threw the inspection hole. Zero the indicator. Then pry the flywheel towards the rear of the truck. This will give you the play measurement.

Then let us know what it comes out to.

[burnt_servo]

if it is an automatic , i'd give serious thought to a cracked flexplate.

[garywj]

I don't have a dial indicator, so I removed the inspection plate, checked all the torque converter bolts and inspected the flex plate as I turned it over with a wrench, and I couldn't find anything. So I started the engine, and watched the flex plate/converter turn, used a long screwdriver to listen to the oil pan, block, belhousing, tranny cover......now I can't seem to locate it. I'm not really familiar with diesels, maybe it's just a noise you guys might find normal?

[PToombs]

Even with out an indicator, just push the balancer back and forth and guesstimate the play. I saw an 855 with 1/4 inch of play once. Obviously a problem there!