The Stovebolt Site Forums The Shop Area Driveline Clutch pilot bushing vs roller bearing

Why some applications use a ball/roller bearing, and others use a bushing is something I have wondered about for along time.

Awhile back, I bumped into a retired driveline engineer, so I asked him that question. He said that some engineers would specify a bearing, if it was anticipated that the vehicle might be used in situations that required the clutch to be disengaged for extended periods of time. He did not elaborate of any specific applications and I kind of got the feeling that the choice was more subjective, than driven by any hard data.

I have also read that some transmissions need a more precise alignment of the input shaft, requiring a bearing. But that is just internet chatter, and I have no personal experience along those lines.

I am in the bushing camp. I have seen a number of input shafts damaged by bearings. None by bushings.

Edit: Actually, just happen to have transmission in my garage now, with a damaged input shaft...