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Is the purpose of the snap ring to hold the bearing tight to the case?
Technically no. The bearing retainer (snout) holds the bearing to the case.

The large outer snap ring helps set the alignment depth of the input shaft/bearing assembly and helps somewhat to keep the bearing aligned in the bore. Without this C clip the bearing could move further into the case and cause friction issues with the internal parts of the transmission. It should be pointed out that the crankshaft pilot bearing helps to keep the input shaft in alignment with the case. A severely worn (or missing) pilot bearing can help ruin a good transmission case (amongst other things.) Total shaft alignment is crucial for longevity.

The smaller snap ring on the input shaft helps hold the bearing on the shaft. (The bearing is a press fit on the input shaft, which is why we need to remove the input shaft to replace the bearing.)
 

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Just something to note, often the new bearing does not come with the correct external snap ring. The one I used recently was too large to seat in the bore of the retainer, but Dan Williams had included the correct part in the kit. You may have to swap your old one onto the new bearing.

Also, that much RTV has no business on a transmission. If you must, use a thin coating.
 

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Discussion Starter · #25 ·
So upon further investigating, I starting to think the “movement” of the OD of the bearing on the input shaft within the case is the necessary movement that the case allows to slide the bearing in and out of the case. The smallest feeler gauge I have is .04 mm and I can’t get it between the case and the bearing that I thought had excess movement. When the snap ring is pushed up against the face of the case there is no excess movement….when the bearing is pulled out slightly and the snap ring is away from the face there is “movement” of the shaft
 

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Given that measurement, you may be on to something good. .4mm (.0157" decimal) would definitely be too much play but your measured .04mm (.00157" decimal) is probably within an acceptable range as the bearing as the bore is not a true press fit. Note that the width (not the thickness) of the feeler gauge skews the actual measurement.

It's OK to remove the outer C bearing clip and attempt to insert the feeler gauge-nothing will happen to the transmission when doing this. You should not be able to insert any more that the tip (if that) of the .04mm feeler gauge between the bearing and the case (let alone the whole width of the gauge.)

I suggest dropping the countershaft, remove the input shaft, and take some similar photos of the case bore so we can see the machined area where the bearing rests. You want the bore to be parallel to itself, paying the most attention at the front of the case bore as that is the normal wear point if the bearing hasn't spun (very rare.) What you don't want to find is that the bore is bell shaped, wider at the front vs the rear. A visual check is normally all it takes but the proper way would be to check it with a bore mic.
 

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Is there a way to verify if I have the wide or short gears? Is there specific markings that identify which is which?
Externally, no. There is nothing on the outside that 100% verifies the gear set that is presently installed. Variations can definitely occur during decades of use.

Internally, yes and its easy. Remove the case cover plate and locate 2nd gear (First is next to the tailhousing and 2nd is the next one forward of first.) Mark one of the 2nd gear teeth with a crayon (or whatever) and count the # of teeth on that gear.

A wide ratio will have 31 teeth in total. A close ratio will have 28 teeth. There should not be any other variations found in production vehicles.
 
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