Transmission noise

[Lawrence S.]

Hi Guys,

I put a new LUK clutch, pressure plate, TO bearing, and pilot bushing in my car recently. While the transmission was out we also put in a new seal kit in the transmission. Prior to the this work I had no abnormal noise out of the transmission. The car has 64K miles on drivetrain as far as I know. Currently, while the car is in neutral with the clutch pedal not pushed in I have a noise that sounds like it is related to the rotating assembley in the transmission. When the clutch pedal is pushed to the floor the noise is not there. I can also hear the noise in first and second gear but not so much in third and fourth. When I get on the car and want to shift quickly the tranny does not let me do so but otherwise shifts smoothly while normal driving.

Sounds like a input shaft bearing is bad, but what puzzles me is that all was fine until we took the transmission out of the car? Wish I would not had to replace that darn clutch . Let me know what ya'll think this may be. The transmission is a M-20 in a 67 L-36.

Thanks,

Lawrence

[Timothy B.]

Re: Transmission noise

Lawrence,

If you removed the side cover to install a new gasket could the shifting forks or something else in that area be amiss. That's where I would look if there is a shifting problem.

[Keith B.]

Re: Transmission noise

sounds like a bent clutch finger or two

[Edward J.]

Re: Transmission noise

Larry, from what your explaining, it sound like a front input bearing. or something may up with the caged bearing where the input and output shafts connect.

Keep in mind that with the clutch pedal released the only thing that is spinning the input shaft of the transmisson. The T/O bearing is floating because of the clutch return spring is being pulling away from pressure plate by the fork

Did you dissay the whole trans when you resealed?

[Eric D.]

Re: Transmission noise

If the engine is running, and the trans is in neutral, and you take your foot off the clutch pedal, the input is spinning which turns the cluster gear, which turns all the speed gears on the main shaft, but the main shaft doesn't spin if the car isn't moving...

Did you change gear lube in the trans???

If the noise goes away as you go up the gears, i'd look at the cluster gear and pin...

Hope this helps... Eric

[Lawrence S.]

Re: Transmission noise

sounds like a bent clutch finger or two

Keith I was told that by another person today. Would the fingers have to be bent alot to make this an issue?

[Lawrence S.]

Re: Transmission noise

Larry, from what your explaining, it sound like a front input bearing. or something may up with the caged bearing where the input and output shafts connect.

Keep in mind that with the clutch pedal released the only thing that is spinning the input shaft of the transmisson. The T/O bearing is floating because of the clutch return spring is being pulling away from pressure plate by the fork

Did you dissay the whole trans when you resealed?

I only took the side cover off the tranny and put in a gasket. Also put in a new rear seal, front seal, and the seals for the gear shafts. Not sure what that is called.

[Lawrence S.]

Re: Transmission noise

If the engine is running, and the trans is in neutral, and you take your foot off the clutch pedal, the input is spinning which turns the cluster gear, which turns all the speed gears on the main shaft, but the main shaft doesn't spin if the car isn't moving...

Did you change gear lube in the trans???

If the noise goes away as you go up the gears, i'd look at the cluster gear and pin...

Hope this helps... Eric

Eric,

Before we changed the rear seal, it leaked bad and we had put new gear oil in the tranny but it has not been changed real well to be honest. I did try to do this recently but my suction gun tube would hardly make it in the fill hole. Therefore, I could not make the 90 degree bend to get down in the bottom of the case. I still want to do asap, but need to find the right tool to extract the oil. I feel like it may be possible that some metal shavings or trash that was sitting in the bottom of the case was disturbed and found it's way in the gears while I was turning the tranny on its side to put the seals/gaskets in. But just a guess.

Thanks,

Lawrence

[Keith B.]

Re: Transmission noise

Keith I was told that by another person today. Would the fingers have to be bent alot to make this an issue?

when you reinstalled the trans did it take a lot of effort to get it to line up the splines? it only takes a little bit to of them being bent to make a noise.

I did that too on my 66 Chevelle SS396. had a noise of something grinding when in gear and moving and went away when the clutch pedal was depressed. it was quite embarrassing