Re: Manual Transmission Clicking Noise

Posted by DavidPackard On 2021/1/25 22:59:31

TimE: I too commend you on the depth of your investigation. I word of caution however would be the faith you might have in your cage speed calculations in that the radial load on the bearing has a significant impact on the actual cage speed, along with lubrication specifics.

I’ve been reading all of my old ‘Motor’s Manuals’ but haven’t found an easy answer . . . sorry. Actually the trouble shooting guides in the transmissions section were dropped sometime in the late ‘40s or early ‘50s.

Now for a round of ‘twenty questions’:

Is the car equipped with an ‘Econo-Drive’, aka overdrive?

May I assume the first/reverse slider rotates only when the output shaft is rotating, but in your idle case the slider was not rotating, yet the ticking was present? There was no mention whether the noise was present in reverse. I guess I assumed when you used the term ‘idle’; one the car was not moving, two the transmission was in neutral, and finally the first/reverse slider was not rotating? If this is TRUE then everything was rotating except for the first/reverse slider and the output shaft. And then when the clutch was depressed all of the rotation was brought to rest just as you said.


When the clutch is depressed, and the vehicle speed is zero, then all elements within the transmission should come to rest eventually . . . perhaps a few seconds with warm oil, and the normal warm idle speed. The next diagnostic test might be; establish a forward speed in first, and confirm the ticking noise is present. Then with the car still rolling depress the clutch, and note whether the noise is present. If the car is equipped with an overdrive let’s conduct this test twice, once with the OD mechanically enabled (cable IN), and again with the OD mechanically disabled (cable OUT). Considering the noise is also present in second gear this test should be repeated in that gear also. That would make a total of four test cases. To Chris’ point, the purpose of this test sequence would be to isolate whether the noise is generated by the transmission. If the ticking is still there when the car is moving forward (clutch depressed) and it stops only when you brake to a stop.

I’m thinking about the countershaft (aka cluster gear) thrust bearings (bronze washers), and whether the entire cluster gear has excessive fore/aft motion. It looks like there would be an axial force, proportional to torque, on the cluster gear except when the transmission is in third gear. I’m trying to make a connection between cluster gear axial position and the ticking. I haven’t found the service limits on the cluster gear clearance.

Finally, if the ticking is interference between a rotating part and the stationary case then you might find magnetic wear metal in the oil. Same would be TRUE if the 2nd gear cluster and the 1st gear main were interfering. I believe there are drain plugs with a built-in magnetics that might help determine if a gear to gear, or a gear to case interference is causing the noise.

That’s all I’ve got tonight . . . By the way try to catch the TV news tonight or tomorrow. You should see a segment about snow in the northern sections of Phoenix today. We had a bit, but not a lot, of graupel where I live.

dp