As the topic says, I drained the oil in the gearbox and two dowels or roller came out. 0.496" dia and 0.849" long. Any idea what they are? Gearbox is operating perfectly as far as I can tell.
Brian
Let me ask this question another way - is there a 3" or so OD plain roller bearing in a Spicer 4 speed 8844? the only manual I have is what is in the MCI manual and it shows three ball bearings and a double taper roller bearing. Is there any way for anything to fall in from the top of the gearbox, around the shift rods or something? I don't see anything in the manual that looks like these rollers came out of the gearbox (aside from actually coming out with the oil, obviously)...
Brian, the only place I know of that has that type bearing in your transmission is on the reverse idler gear.
Been years back when I rebuilt one
good luck
Thanks, this has me baffled and obviously worried. By idler gear, do you mean the reverse sliding gear? In my poor manual there are a couple of needle roller bearings, but nothing that looks like a big roller bearing.
Thanks, Brian
Well, after a lot of digging and searching, it seems that the MCI manual that states in several places that the main and countershaft bearings are ball bearings is wrong. At the very least, the rear countershaft bearing in this gearbox is a roller... with rollers that look a match for the ones I found...
I spent the afternoon under the bus, and took the side covers off and looked inside. Prior to that I flushed the box with clean oil and filtered the drained oil looking for junk. If there is a bearing breaking up, it's doing it remarkably neatly - the inside of the gearbox is clean as a whistle, absolutely no trash resembling bearing cages or anything else for that matter. The only bearing that rollers could actually get out of is the rear countershaft bearing, since the main shaft bearings (if they are rollers too, in contradiction to the manual) have the drive gear and first gear smack up against the bearing and the rollers would have a time and a half getting past them. So I took off the bearing cover for the rear countershaft bearing and looked at it. Clean as a whistle, tight, and rather more importantly with all of it's rollers present and accounted for... :o Doing this work it became obvious that someone had been inside the gearbox before, either a rebuild or a bearing change, and the decision is that the two rollers got left behind by accident when this work was done. The combination of an intact bearing and absolutely no trash inside the gearbox, and the fact that it shifts fine, stay in gear and doesn't make obnoxious noises means I will button it up and carry on busing...
Many thanks to Luke who called his rebuilder to get the word on the bearings.
Cheers, Brian