Tomarrow I am taking my truck into the dealership for a CEL and to have them listen to my clutch for a second time. The sound is more prevalant at idle with the truck in neutral, clutch out, it sounds like a fine grinding/spinning noise and once you push the clutch in it spins down and goes away. You can also hear it when you shift threw the gears and especially in 5th and 6th. So is this a T.O. bearing going out?

 

sounds like it

 

the throw out bearing only spins when the clutch is disengaged.......pedal In.


IE the throwout bearing only starts spinning when you step on the pedal and the bearing presses against the pressure plate fingers.

its not possible that the noise you have is the throw out bearing.

sounds more like input shaft bearing ........I'd have to think it through a little more though

 

Thanks, I just was not sure what it was. I have searched this site as well as the Cummins forum for info and not finding any answers.

 

Well im not too sure because i dont have a manual transmission in my truck, but i had a car that i changed the clutch in and put a new throw out bearing in and i just didnt get it in there right and it made that noise until i aligned it right. It did it exactly like you said. I just had to tear it back apart and get it on there right as it sorta moved when i put it back together.

 

When you disengauge the clutch the T/O bearing will be spinning all the time you have your foot on the pedal. In fact some newer vehicles have self aligning t/o bearings that actually lightly ride the clutch diaphram so there may be some contact even when it's engauged. When you disengauge the clutch the pilot bearing will be turning. It sounds possibly like the input shaft bearing in your transmission. If the truck is idling in neutral with the clutch engauged the input shaft bearing is turning. If when you disengauge the clutch the input shaft would "spin down" or rotate a few turns and stop. Anyway, please let us know what it is, I am very curious.

 

Well of course the dealership said it was normal and "we even had the transmission guy take a look at it and he said it was normal" . I think I am just being brushed off. Anyway I am going to have the mechanics at my fire department I work at take a listen and see what they think. I will keep you posted.

 

Typical. Isn't it amazing that even after spending $40,000 on a truck they still act like that? Be persistent and ask to see if any other new trucks make that noise.