77 c10 tranny "squeak"

[kamp77]

my daily driver 77 c10 has this random squeak. it does it at certain mph in certain gears. like 10-15 in 1st 30 in 2nd and 35-40 in 3rd. it goes away in neutral or when i have the clutch in, or as soon as i go over/ under those mphs. the engine is a 250 l6 with a 3-speed column shifter.  also it doesnt do it every day, but doesnt seem to coralate with temperature.  thanks for any help and info

-matt

[Captkaos]

Throwout Bearing?  Can you tell where the sound is coming from?

[Blue 82]

Another vote for the throwout bearing
this will turn to a squeal later

[kamp77]

thats what i thought. It sounds like its coming from the trany.  When i do the throw out shouldnt i just replace the clutch?

[ccz145a]

shouldnt i just replace the clutch?

and pressure plate as long as your in there.

[kamp77]

What does it meann if its an intermitent thing while driving. It also does it in neutral when i blip the gas now

[VileZambonie]

You need to find out where it's coming from. Don't start throwing parts at it. If it was the release bearing it would do it without the truck moving too. Check your u-joints, and see if you can duplicate it jacked up.

[kamp77]

I decently know my way around a car but im still a newb, what are u joints. Dont they connect the driveshaft and differential?

[Captkaos]

When it starts squealin' just barely push on the clutch pedal to see if it stops.

[VileZambonie]

yes they are on the driveshaft.

[Jay2D2]

In theory the u-joints should not squeak in neutral.
Like Vile said jack all 4 wheels and then while youre in the truck have a buddy lay down beside -NEVER UNDERNEATH - and see if you can recreate the noise and have him pinpoint more of its location.

It an never be stressed enough to never go underneath a vehicle thats jacked up while running. Weve all heard the stories of a car collapse on someone. Some of you may even know someone who it happened to, I do.

[kamp77]

how expensive would u joints be to fix?  also today it didnt do it at all... its the randomness that really confuses me

[ccz145a]

less than $30 per joint.

get the ones with a grease fitting.

[kamp77]

Ok. So my best bet is to get under there and isolate where it is. And if its from the bell housing its throwout bearing and if its from the end of the drive shaft its the u-joints?

[kamp77]

so being the rookie that i am i figured out that its not a drivetrain issue at all.... it was a belt . anyway thanks for all the help and good info