marky mark

I notice that my M-20 4 spd seems to be making a noise while in neutral at idle. Sounds like a mechanical noise but not real,real loud, just enough to notice.Not so much a tapping sound as a loose rattle, although that may not be the best description as it's hard to tell over the exhaust. It has fluid and shifts fine. I had the tranny rebuilt and I'm wondering if that might be the cause?

Is this a natural thing with these trannys? :flag :chevy

Merry Christmas, Mark

63Banshee

Are you sure the clutch is fully disengaging and/or it isn’t the throw-out bearing you are hearing?

Bob Jenkins

Did you also re-install the return springs in the right locations? Sometimes you can get vibrations in the linkage at idle. It could also be the throw-out bearing making noise. Did you replace it when you rebuilt the transmission? My car's throw-out bearing started making noise after the car sat for several months. Oneday the noise just stopped... :confused:

454Big

Check linkage for loose parts.
I had the problem when the shift rods directly at the tranny were loose.
Also check if the problem occurs in cold and warm condition.

marky mark

It could be the throw-out bearing I suppose, but that was new also. It actually sounds as though it's coming from the transmission case itself. I was and should have sent it off to "4-Speeds by Darryl" but I didn't. DOHHHH !!!

Merry Christmas,

Mark :flag :chevy

69classchass

Mark,
When your hearing the noise , De-press the cluch, and see if the noise doesnt change or stop, Shift the gears, then back to neutral and see if the noise doesnt change. If the noise persists through these checks, Get under there with some kind of stethoscope and see if you cant isolate the noise.
I had a thump thump kind of noise starting up cold at idle. It went away when I changed to sidepipes :D..
seriously it was just the flywheel whirling, I wasnt bothered because it only did it cold, for a minute ,so I disregarded the flywheel being out of balance
TC

marky mark

Allright, I'll try that and see if I notice a difference. Thanks. Mark :flag :chevy

john73bb

Mine had done this for as long as I have owned the car. I replaced the clutch and throwout bearing not too long ago, and it didn't change a thing. Most days I don't hear it at all, and then once in a while it comes back. I also presume it is something inside the tranny -- I rebuilt mine also. If you find out what it is, please let me know too! :)

marky mark

Will do John73BB. I've got to take it by the guy who did the rebuild as the rear seal is already leaking. I'll have him listen to it and get his opinion. It may be nothing, but I can't imagine GM would design/build a tranny that made noise.

Regards, Mark