Tranny/clutch noise

[chicklin]

I know I need to adjust my clutch pedal as it has to be nearly all the way up before it engages, but I've got another issue that may be related.

If I put the tranny in neutral while the truck is running, it still puts a load on the motor...not enough to move the truck, but there's definitely some resistance as I can hear the motor wind down a little. By that, I mean if I push the pedal in, the noise goes away and when I let it out I hear some noise from the tranny and motor loads up.

What could be causing this? Something with the throw-out bearing? Any way to fix this without dropping the tranny? Think it's related to the clutch pedal needing adjusted?

[Barrman]

The noise could be the throw out bearing or the input shaft for the transmission. If the engine idles down with the transmission in neutral, I lean more toward the transmission being dry or messed up bearings.

Now, if you just started it up with the clutch pushed to the floor and have no noise. Then let the clutch out and a noise appears and the idle drops. How cold it is outside? Any time it is below around 50 or so any of my vehicles will pull the idle down until the transmission oil warms up some. The noise on mine with a 7 month old throw out bearing only happens if I haven't driven it in a week or so. Then after the first few minutes, it is gone until the truck sits a long time again.

I would say your transmission needs to come out because it sure seems like the clutch is worn (high pedal), your throw out bearing is worn or just plain dry (noise) and you might have input shaft issues with your T-98 (excess drag.)
That make sense?

[chicklin]

I would say your transmission needs to come out because it sure seems like the clutch is worn (high pedal), your throw out bearing is worn or just plain dry (noise) and you might have input shaft issues with your T-98 (excess drag.)
That make sense?

A little, yes. I get the clutch wear/high pedal part. It doesn't slip any, although I guess it wouldn't necessarily.

I think I get the bearing part. The input shaft is still turning in neutral, right? So the noise is just the dry bearing. Any way to lube that, or is it just replace?

What about the engine loading up? Drag caused by the dry bearing?

[chicklin]

Also, yes, it does seem to be worse when it's cold or has been sitting a while.

I used to have a CJ5 that the clutch would stick so bad that you had to start it in gear to break it free. Seemed to work fine, though. I think it made the same noise in neutral. Sounds like one of those things that, while it needs to be fixed, I can probably just run it until it gets worse.

[amphi]

I get the clutch wear/high pedal part. It doesn't slip any, although I guess it wouldn't necessarily.

That's correct – it might not slip but your throw-out bearing might still be riding on the clutch fingers. A high grabbing pedal can be just like a partially depressed pedal where one is riding the clutch. It should be adjusted to catch closer to the floor insuring full disengagement when at the top of pedal travel.

The input shaft is still turning in neutral, right?

Right: And so are most of the other gears in the transmission.

#39 in the below drawing is the input shaft. The small gear on this shaft is meshed, at all times, with the large gear #73 on the countershaft - the whole countershaft spins with the input shaft. #43 and #47 mesh with the countershaft so they also spin even when in neutral.

Also, yes, it does seem to be worse when it's cold or has been sitting a while.

This slowing of the engine will happen in cold weather but yours might be dragging more than normal.

I can probably just run it until it gets worse.

That is exactly what I would do!!

Hope I didn't give too much info with the drawing etc. -- just wanted to show it could be more than one bearing dragging and making noise.

[chicklin]

That is exactly what I would do!!

Hope I didn't give too much info with the drawing etc. -- just wanted to show it could be more than one bearing dragging and making noise.

Thanks for all the info, that was a great little tutorial. I confess, I understand at a high-level how a transmission works, but I've never taken time to understand the guts.

I think I'll just adjust the pedal to compensate for the (most likely) worn clutch and then drive it 'till it breaks.

[amphi]

You are welcome!!

By that, I mean if I push the pedal in, the noise goes away and when I let it out I hear some noise from the tranny and motor loads up.
What could be causing this? Something with the throw-out bearing?

One more thing -- A bad throw-out bearing is most likely to act just the opposite of what you describe.

When a properly adjusted clutch is fully disengaged the throw-out stops spinning completely because it is slid back away from the spinning pressure plate fingers. Yours might not be doing this because of the high pedal.

Just adjust the clutch and drive it - watch for heat and listen for the noise to get worse.

[DAVEJ]

You don't want to drive it too long making noises ,they can explode. Knew a guy who lost part of his foot when that happened. Be careful, too soon is better than too late!!!

DJ

[amphi]

You don't want to drive it too long making noises ,they can explode. Knew a guy who lost part of his foot when that happened. Be careful, too soon is better than too late!!!

DJ

Well that's a good point there Dave.

Better advice than mine.