I currently have a 2003 C5 non-Z06 with around 145,000 miles. Mostly highway miles. I purchased the car about 1 1/2 years ago with around 100,000 miles which were also mostly highway miles. Now the current issue:

Loud chattering (some might say grinding) noise whenever I put the car into gear at a mid to high rpm. For example, this noise will occur if I try to get the car going from a stop, at anything higher than 1,500RPM. If I slowly get it going from 1,000RPM, the noise will not occur. The same sound occurs if I'm going 10mph and I try to get into 2nd gear at... let's say 3000RPM or so.



Some other facts that might help with a diagnosis:

Once the noise starts, it will continue even after I pull it out of gear. The noise will only stop after I let off the clutch pedal.

I noticed that it is getting a little harder to get the car into gears since this issue first started. But absolutely no actual grinding when I try to get into gear which makes me think that it is not a transmission issue.


I took it to a shop and they think it might be the teeth on the shaft that comes out of the torque tube. A lot of shops have quoted me $700+ just to take a look at it because they are saying they have to undo the whole rear suspension to take a look at the transmission.



Any help would be greatly appreciated. Please let me know if you need any other info for a diagnosis. THANKS!!!

 

What do you mean by "let off the clutch pedal"? Pressed down or pdal full up?
Has the clutch ever been replaced?

They are correct that the rear suspension has to come down.
If I were to guess, it could be clutch related or the propshaft bearing or coupler has gone. If the noise goes away with pushing in the clutch pedal, then more likely clutch related.

 

I'm thinking throwout bearing and or worn out clutch. At 145k, you are past time to change it if it has never been done.

 

by "let off the clutch pedal" I meant, full up. and i have not changed the clutch. but i bought the car with 100K so there's no way for me to know if it was done before that.


thank you for your responses. any help is greatly appreciated!!

 

Well, my guess from out here in cyber space would be the through-out bearing or broken clutch spring finger. I believe you are looking at a clutch replacement. If it were me I would be replacing everything with the clutch including the master and slave units, all bearings and even a new flywheel.

Regards,,