Ok so my truck has started to make a strange noise. The noise sounds like a squeaky rattle and is audible while engine is idle or at low cruising speeds. The sound may be there during higher speeds, but I cannot here it because of the engine noise. Anyway so the sound goes away when the clutch is depressed and starts again as soon as clutch is let out. Anyone have any clue as to what this could be? Thanks for the help guys.
-Ray

 

my guess is thrust bearing.

 

That is the ever popular manual transmission bird chirping. Mine does it too, as well as 5,000 other people who have complained about it. What's weird is there seems to be several possible causes..throw out bearing dry, front transmission bearing dry, clutch fork dry (where the slave cylinder contacts it). Good luck tracking it down. I've learned to live with it.

 

I've heard Redline MT90 makes it go away, but I have yet to try it. I've got the birds for now as well.

 

Jonathan,
A different MT fluid may indeed make a MT shift better/slicker/whatever, but the issues associated with this common problem are situated outside of the actual gearbox. Throw-out bearings, clutch forks, and the like are located in the bell housing and do not benefit in any way from a change in MT fluid. These items have a certain amount of factory lubrication that eventually dissapates from heat, clutch dust, and use.

Andreas