98 4 cyl w/manual noise. Help.

[Darren94]

I picked up a 98 b2500 with 179k and i have noticed that when i let of the gas and let the truck coast in gear, there is a consistent humming sound coming from the trans. The noise is louder with higher rpm and quieter with lower rpm. It also seems to occur in all gears but is most noticeable in 1st, 2nd and 3rd. However, if i press in the clutch, the noise will always stop.

The previous owner recently had a new clutch, TO bearing, flywheel and slave cylinder installed and i did notice that the TO bearing is a bit loud when idling.

Any ideas? (i changed the fluid and there was a small amount of filings on the plug but, the fluid looked clean)

 

[Rembrandt]

My prob started this same way and it has gotten worse, almost grinding now. I have recently changed all the clutch components and TO bearing. I have been told it is the input shaft bearings in the trans, I have the exact same truck. So I guess a rebuild of the trans in the very near future is in order