Manual tranny noise

[TallPaul]

2001 Chevy S-10, 2.2L 5 speed. Transmission fluid was checked last month and is full and clean. When accelerating in first up past 25 mph (sometimes after 20 mph), there is a sound like a metal spring whirring around, rather high pitched. Sounds more like a circular metal piece that is part of the assembly rubbing on something, not a loose chunk bouncing around. Only comes in at higher rpms also in second gear sometimes, prob never take 3,4 or 5 high enough to hear it. What could it be?

I am thinking to change out fluid and install Redline MTL. No thicker that stock fluid, but more antiwear, maybe help?? Can't hurt, may help, at 78,000 miles not a bad idea to change out fluid anyway, no?

 

[JHZR2]

I can hear a whirring if I put my bmw's mt into gear with the clutch pressed. As I understand it, that whirring sound is the throwout bearing.


I'd imagine that in your case, it is still spinning but unloaded. Maybe it's related since the sound is similar? As I understand it, this bearing is one of the weaker links.

 

[TallPaul]

Yes, I thought of the throwout but figured it would only make noise with the pedal depressed. But if it is something that is going to fail, better the throwout than the transmission, eh?

 

[SteveSRT8]

Throwout bearing can still do damage to the trans input shaft if neglected.

Any noise is a worthy concern.

 

[TallPaul]

Just talked to the mechanic who did my slave cylinder in the Ranger earlier this year. He said that the throwout will not make noise once the clutch is engaged because it is not moving. I know it is moving but the same as I am moving now sitting in my chair, I am only moving because the earth is turning.

 

[NHGUY]

I had an 89 S10 5-spd,and at 21,000 miles I needed to do a clutch job.The TO bearing had seized,worn the input shaft cone on the trans,and wore 1/2 way thru the clutch cover diaphram fingers.Seems the TO bearing was spinning for every engine revolution even with the pedal released.Eventually it ran hot and out of grease and started spinning on the cover fingers.Poor designed hydraulic setup.One of the many reasons there are no GM vehicles in my future (until I get Alzheimers).

 

[demarpaint]

Originally Posted By: SteveSRT8
Throwout bearing can still do damage to the trans input shaft if neglected.

Any noise is a worthy concern.


+1

 

[TallPaul]

Originally Posted By: NHGUY
I had an 89 S10 5-spd,and at 21,000 miles I needed to do a clutch job.The TO bearing had seized,worn the input shaft cone on the trans,and wore 1/2 way thru the clutch cover diaphram fingers.Seems the TO bearing was spinning for every engine revolution even with the pedal released.Eventually it ran hot and out of grease and started spinning on the cover fingers.Poor designed hydraulic setup.One of the many reasons there are no GM vehicles in my future (until I get Alzheimers).


Okay, what noises was it making and when? Was there anything in the feel? Did the clutch engage/disengage properly?

 

[TallPaul]

Correction, son says it only made that noise in 1st gear, never in 2nd or any other gear.

 

[mechtech2]

Originally Posted By: TallPaul
Just talked to the mechanic who did my slave cylinder in the Ranger earlier this year. He said that the throwout will not make noise once the clutch is engaged because it is not moving. I know it is moving but the same as I am moving now sitting in my chair, I am only moving because the earth is turning.


The front of the TB still turns relative to the rear part - it can make noise when depressed. [Unless you have a '50s VW or Porsche with a carbon faced bearing!]

An trans input bearing is likely to make a noise when the clutch is depressed .

 

[TallPaul]

Whelp, I changed out the fluid. Out went the 9.4 cSt GM Synchromesh and in went the 10.4 cSt Redline MTL. We only drove it 5 miles since the change but my son said the shifting felt better, tighter. I attribute that mostly to the thicker viscosity. But the Redline MTL is going to provide other benefits to that transmission, for sure. So far haven't heard that weird noise but then he didn't want to run first gear up to 30 mph on a relatively cold engine. In due time we will see.

This is the 2001 S10 5-speed 4-banger. At 78,000 miles the Synchromesh fluid was clean, clean, clean. A blotter only showed a ghost of a ring.