These two designs are very similar and sick examples show similar symptoms. The following notes may give you some idea of what to expect when tearing down your transmission.

All gears missing but speedometer functions
	Broken mainshaft or driveshaft yoke.
All gears missing and speedometer does not function
	Broken maindrive or clutch.
All indirect gears missing/direct gear (4th) present
	Broken teeth on maindrive or countershaft cluster.
All indirect gears present/direct gear (4th) missing
	Broken clutching teeth on maindrive or sliding clutch.
Only one gear missing/others present
	Broken teeth on mainshaft gear or countershaft cluster.
	Broken clutching teeth on mainshaft gear or sliding clutch.
Transmission locked in all gears
	Worn or bent shift fork.
	Worn or broken synchronizer rings.
	Worn or broken detent spring.
	Worn or broken interlock.
Transmission locked in all gears but one
	Seized mainshaft gear.
Persistent mainshaft oilseal leak
	Worn universal joint.
	Bent or unbalanced driveshaft assembly.
	Worn mainshaft bushing.
Noise with the transmission in neutral
	Low oil level or improper oil used.
	Worn bearings.
	Worn countershaft thrust washers.
	Loose material in transmission.
	Worn or spread case (a particular problem in Muncies).
Noise in all gears/quietest in direct gear (4th)
	Low oil level or improper oil used.
	Worn bearings.
	Broken or damaged maindrive or countershaft drive teeth.
Noise in one or more indirect gears
	Broken or damaged mainshaft gear or countershaft gear teeth.
	Broken or missing snaprings, washers, or spacers.
Gear clash in shifting
	Clutch not releasing fully.
	Bound clutch pilot bushing or bearing.
	Worn synchronizer rings or mating gear cones.
	Worn or broken synchronizer struts.
	Broken or missing synchronizer rings.
Hard shifting
	Worn or bent external shift linkage.
	Worn or broken synchronizer struts.
	Broken or missing synchronizer rings.
	Excessively heavy oil used.
Jumps out of direct (4th) gear
	Misaligned transmission case or clutch housing.
	Low oil level or improper oil used.
	Worn clutch pilot bearing or bushing.
	Worn clutching teeth or sliding clutch.
	Worn or broken detent spring.
	Worn or bent shift fork.
	Excessive maindrive endplay.
	Worn maindrive bearing.
Jumps out of one or more indirect gears
	Low oil level or improper oil used.
	Worn mainshaft pilot or pilot rollers.
	Worn clutching teeth or sliding clutch.
	Worn or broken detent spring.
	Worn or bent shift fork.
	Excessive mainshaft endplay.
	Worn mainshaft bearing.
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