TRD Short Shifter Rattle Noise, It's Normal?

[banpei]

I have conducted two experiments: I installed more mass to the flowerknob and then installed the "lightweight" TRD knob. In both cases, the rattle remained at around 5K rpm. In the case of the heavier, the rattle was more loud while the lighter was softer. This does make sense if you think of the shifter as a pendulum. I'm not increasing the shifter's length (that much) with the flowerknob, so the natural frequency remains the same.

The good news is that I also found out why the TRD short shifter was rattling:

When I held my TRD short shifter in my hands, I could feel there was slight play in the vertical direction.
The TRD base plate doesn't feature a bushing, not even a copper one! It's actually metal only, which means the shifter itself is in direct contact with the retainer plate. You can see in the photo that there is pitting. I suspect that, even though enough grease was applied, the cup on the retainer plate wore down. When there is a slight play in the shifter assembly, the higher revs will make the shifter rattle. The rattle will then only make things worse as it will pit the cup even more.

My conclusion is that if you have a TRD short shifter that rattles, it's probably because of wear. It doesn't mean the TRD short shifter is broken, on the contrary: apart from the rattling noise it works just fine. I think a TRD short shifter that rattles can probably be fixed with a shim as this would remove the excess play.