The Stovebolt Site Forums The Shop Area Engine Shop Stick shift rattle

Hello all,

I just redid all my gaskets on the tranny (ie: top cover, PTO cover and the 2 circled one on the back) and as I did so I looked in there to see what shape the gears are in. They all look good and there was no metal shavings in the gear oil that might suggest any bad omens.

MY question is this: What might be causing the "rattle" sound that seems to eminate from the stick shift lever?
-The rattle is there even when I have my hand on the stick and I notice that it disappears when I go in to 4th gear (then the only sound is the high pitched hummm) ( I also heard these are inherently noisy anyway). I have the 4 speed (granny low) sm420 trans.

Thanks for your help!
Shane Hamilton
Warrensburg, MO

Those 4 speeds do rattle some with the rough cut gears. Does it go away with an increase in rpm ? What weight gear oil did you use ? I would use a good 90 weight, like Napa # 75-210 .Let us know how you make out.

When you're running in 1st., 2nd., or 3rd. gear, power is being transmitted through the input shaft, cluster (counter) gear, reduction gears, and then to the output shaft. In 4th., the power goes straight in and out, and while the countergear is still turning, it's not loaded at all. It's possible the needle bearings that support the countergear on its shaft are worn, or it's more likely that you're just hearing the normal noises of power going from one gear to another. It's going to be VERY noisy in granny gear, because that one has straight-cut teeth.
Jerry