Lately my truck has been making this screeching sound that goes away when I push the clutch in. It happens in any gear including neutral but it does not happen all the time. It happens more often in the cold and sometimes it will go away for no reason. My initial guess was throwout bearing but those usually make noise when the clutch is pushed in.

Important to note, the truck has 194k miles on it with the original clutch. I know a clutch replacement is in my future and depending of this noise it may be sooner. When I do replace the clutch I will also replace the rear main seal, the slave cylinder, and the pilot and throwout bearing.

 

The clutch release bearing on these trucks is always in contact with the pressure plate at all times.
That means the bearing is spinning all the time, so noise comes when there is no load on the bearing.
When the bearing is loaded, the noise stops.
The throw-out bearing comes with the salve cylinder, so you will be forced to get a new one as well.
It's a good idea anyway since the entire transmission has to be dropped to get at things.

 

Yes, +1

Try barely pushing on the clutch pedal next time it squeals, so add just a little pressure to throw out bearing, if noise changes then you are correct, throw out bearing is the problem.

Pilot bearing allows flywheel/crank to turn at a different RPMs than the input shaft, so when clutch is engaged, foot off the clutch pedal, the flywheel and input shaft are spinning at the same RPM so no noise would be likely.
When clutch pedal is down then input shaft can change RPMs to match gears/rear wheel RPMs, so that is when a failing pilot bearing is likely to make a noise.

 

I guess it is the throwout bearing then. I have noticed that the noise goes away with just a little pressure on the pedal. I guess I will be doing a clutch job soon, probably once the semester ends.

 

My old beater B2200 Mazda is doing the exact same thing.
Apply just a little peddle pressure and it stops.

 

Well the throwout bearing noise is coming and going but now it is happening with the clutch pushed in.

More importantly I am having a hard time shifting gears. My guess is the slave cylinder is going out.

 

Yea, you'll be replacing it very soon. Mine was making a noise that I only noticed when the truck was off and I pressed the clutch in. My interior is sound deadened, so I couldn't hear anything while driving. About two weeks after I noticed the noise, the truck all of sudden wouldn't go into gear. I had to shut it off and wait a few seconds to get it in gear, and then start it in gear. Went straight home and replaced everything that night.

 

Alright new clutch, pressure plate, slave, throwout bearing, and pilot bearing are in. I also did the rear main seal and the transmission fluid. Everything is back to normal. Glad to be driving my truck again but will miss borrowing my friend's Miata and my mom's manual Corolla.

 

Good work

Thanks for the update