Attn: Transmission & clutch gurus
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I have a 2004 GTO with a 6 speed manual transmission and recently it started making a horrible noise. There is a knocking noise coming from what sounds like the transmission area.
The noise only appears while driving the car and gets faster as the car goes faster. It is not present when the car is in neutral or when the clutch is depressed. It even appears to go away when I let off of the gas while driving.
Any ideas?
The noise only appears while driving the car and gets faster as the car goes faster. It is not present when the car is in neutral or when the clutch is depressed. It even appears to go away when I let off of the gas while driving.
Any ideas?
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What kind of knocking? real fast, real slow, loud, metallic sounding, thumping, etc....?
When say you are driving @ 70 MPH, and you put it in neutral, sound still there? Go away?
What about sitting still, clutch in (or in neutral) and you rev the motor, sound there, or no?
Only at speed? How fast before you start noticing it?
When say you are driving @ 70 MPH, and you put it in neutral, sound still there? Go away?
What about sitting still, clutch in (or in neutral) and you rev the motor, sound there, or no?
Only at speed? How fast before you start noticing it?
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It is a pretty loud noise. It can be heard over the headers. It is kind of a thumping noise. Speed sensitive. The faster I go, the faster the knock/thump.
I haven't had the car up too fast since I heard the noise. The noise starts pretty much as soon I start moving. At 40 mph, if I put it in neutral the knocking goes away. It also goes away if I push in the clutch while driving. It even seems to go away if I let off the gas while driving.
It does not make the noise while sitting still, even if I rev it up.
I put the car on jack stands and ran it in first and second up to about 3000 rpms and didn't notice the noise then either. I was nervous to give it much gas though in fear that the torque may knock it off of the stands.
I am at a loss.
Throwout bearing?
Input shaft?
I haven't had the car up too fast since I heard the noise. The noise starts pretty much as soon I start moving. At 40 mph, if I put it in neutral the knocking goes away. It also goes away if I push in the clutch while driving. It even seems to go away if I let off the gas while driving.
It does not make the noise while sitting still, even if I rev it up.
I put the car on jack stands and ran it in first and second up to about 3000 rpms and didn't notice the noise then either. I was nervous to give it much gas though in fear that the torque may knock it off of the stands.
I am at a loss.
Throwout bearing?
Input shaft?
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A thumping that picks up with the vehicle speed and is not gear sensitive sounds like debis / chip in the headset gearing of the trans. Thats the input gear/ clustergear mesh.
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Not necessarily. My car had a slight knock that sounded like tranny.... Same indications as yours..... A few burnouts later and it turned out to be a twisted pinion shaft..... (on the POS 10bolt)
FWIW looking under car for a loose motor/tranny mount is good advice.
I hope its not internal.....
Good luck!
FWIW looking under car for a loose motor/tranny mount is good advice.
I hope its not internal.....
Good luck!