Rattling trans/clutch sound at idle with engaged clutch only?
01-08-2009, 10:13 AM
#1
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Rattling trans/clutch sound at idle with engaged clutch only? I've got a minor rattling sound going on at idle, but as soon as I push the clutch pedal in, it disappears. I wanna say I've heard that it could be a throwout bearing, does this sound right? If so, what kind of labor/parts am I looking at to repair that?
Also, what could cause an increase in volume of regular transmission noise? It could just be me, but I swear my transmission's regular operation noise has gotten louder recently. I mean, no sounds that are out of the ordinary, just louder.
Thanks in advance for any help.
Also, what could cause an increase in volume of regular transmission noise? It could just be me, but I swear my transmission's regular operation noise has gotten louder recently. I mean, no sounds that are out of the ordinary, just louder.
Thanks in advance for any help.
01-08-2009, 07:49 PM
#2
You can check to see if it's a throwout bearing or trans with a simple test.
To check the throwout bearing don't push the clutch pedal all the way down, just push it enough to put pressure on it and take up all the slack. This way the trans still turns, so if the noise goes away, it's the TO bearing.
It sounds like a trans problem to me. Loose parts will rattle around at idle, plus you say it makes more noise other times too. And when you push the clutch in it goes away, thats because the trans stops turning.
I'd just change the fluid first, not that this is the answer but drain it in a clean container and look for metal or anything else in it. If you find a lot of metal you have your answer right away.
Thats just my opinion without hearing the noise.
To check the throwout bearing don't push the clutch pedal all the way down, just push it enough to put pressure on it and take up all the slack. This way the trans still turns, so if the noise goes away, it's the TO bearing.
It sounds like a trans problem to me. Loose parts will rattle around at idle, plus you say it makes more noise other times too. And when you push the clutch in it goes away, thats because the trans stops turning.
I'd just change the fluid first, not that this is the answer but drain it in a clean container and look for metal or anything else in it. If you find a lot of metal you have your answer right away.
Thats just my opinion without hearing the noise.
01-09-2009, 09:10 AM
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I appreciate that!!
I already changed the fluid, and it didn't seem to help. I didn't see any foreign material in the old fluid, but it was horribly, horribly black.
Also, I tested the clutch pedal distance needed to stop the rattling, and I do have to push the clutch in nearly to the floor (way past just taking out the slack) for the sound to stop. The rattling at idle is hardly noticeable, but if it is tranny problems, obviously that concerns me. Now, forgive my ignorance, but when you're in neutral, the tranny isn't turning, is it? How could the problem be the tranny if it's in neutral at idle?
One other thing worth mentioning is something strange that has happened to me only twice when the past fifteen months or so: my tranny has totally seized up and locked me in gear. Both times, I turned off the engine and kept pumping the clutch, and finally it freed up, but it was still hesitant to go into gear for several minutes. Within five to ten minutes, the hesitance disappears and it behaves 100% normally. And remember, this has only happened twice in over a year.
One of my buddies offered this theory. Hydraulic fluid in the clutch master cylinder line is boiling when the car gets hot due to it being in close proximity to my longtube headers. What do you think about that?
I already changed the fluid, and it didn't seem to help. I didn't see any foreign material in the old fluid, but it was horribly, horribly black.
Also, I tested the clutch pedal distance needed to stop the rattling, and I do have to push the clutch in nearly to the floor (way past just taking out the slack) for the sound to stop. The rattling at idle is hardly noticeable, but if it is tranny problems, obviously that concerns me. Now, forgive my ignorance, but when you're in neutral, the tranny isn't turning, is it? How could the problem be the tranny if it's in neutral at idle?
One other thing worth mentioning is something strange that has happened to me only twice when the past fifteen months or so: my tranny has totally seized up and locked me in gear. Both times, I turned off the engine and kept pumping the clutch, and finally it freed up, but it was still hesitant to go into gear for several minutes. Within five to ten minutes, the hesitance disappears and it behaves 100% normally. And remember, this has only happened twice in over a year.
One of my buddies offered this theory. Hydraulic fluid in the clutch master cylinder line is boiling when the car gets hot due to it being in close proximity to my longtube headers. What do you think about that?
01-09-2009, 10:09 AM
#4
If you have a manual trans with black fluid there is a problem.
With the trans in neutral, engine running, clutch pedal up--the input shaft turns, and that turns the cluster gear.
If the engine is off, it should pull out of gear even with the clutch pedal up, if it's not on a hill or anything.
I don't know about the fluid boiling, I've heard of that happening, but it's never happened to my car, and I've driven it 16 hours straight a few times.
It wouldn't hurt to flush the fluid out.
Thats all I've got.
With the trans in neutral, engine running, clutch pedal up--the input shaft turns, and that turns the cluster gear.
If the engine is off, it should pull out of gear even with the clutch pedal up, if it's not on a hill or anything.
I don't know about the fluid boiling, I've heard of that happening, but it's never happened to my car, and I've driven it 16 hours straight a few times.
It wouldn't hurt to flush the fluid out.
Thats all I've got.
