The Stovebolt Site Forums The Shop Area Engine Shop gearbox mainshaft bearing

Another question folks. I have a 1941 with a four speed crash box. I have the uni-joint off at the moment. There is some movement, both up and down and side to side when I grab the mainshaft. I'm assuming that the mainshaft bearing should be replaced. There is however also movement when I grab the shaft and pull and push it. Is it likely therefore that the pilot bushing will also need to be replaced?

Thanks

Bob

Hi Bob,

Up and down is a no-go, your bearings should be replaced. Do both bearings (inpout and output shaft)because if one bearings fail it also hurts the other one - most of the time.

You have to disassemble the whole thing while it is out of the car, also use the chance to replace the syncros.

The pilot bearing is in the crank shaft of the engine and it is a good idea to replace that too while the tranny is out, it is a cheap part anyways. It only controlls side movement, not back and forth because it looks like a fat ring.

You will be surpriced how smooth shifting is, after all is done.

Frank

Thanks Frank,

I'll be taking the gearbox out this weekend. This is the earlier four speed gearbox so its a non syncro one. I think that you are right that it would be sensible to replace all the bearings and bushings while I've got it on the bench. I haven't been inside one of these boxes before. Thank goodness for the workshop manual.

All the best

Bob