TR6 Countershaft bearings

[DanB]

Are the needle bearings and the cage bearings on the countershaft of a TR transmission supposed to be interchangeable? The serial number on my case was a later number, so I ordered the caged bearings that Moss indicated, but they would not fit. Another club member went to the June event in Virginia and took my old bearings along with the ones I had bought. They exchanged it for a bunch of loose needles. He had my old caged bearings for them to look at. Can I use the loose needles?

 

[JerryVV]

What style bearings were originally installed? Need more information. TR3 used loose needles, TR3B, 4, 4A and maybe 250 used caged needle bearings. TR6 changed to different style of caged needle bearing that used the OD of the counter shaft as it's bearing surface.
So your question can't be answered without more information.
Hope this helps get the correct information flowing.

 

[DanB]

The transmission case number is CD37996. Based on that number I ordered Moss part#848-640, I think it was. Anyway, they would not go into the piece the old ones came out of, at least not without significant pressure. Since Kevin was going to the event at Moss, I asked him to take my original shells and the new ones and see if I had the right parts, or exchange them. They took the cage bearings I bought back and gave him the loose ones. Someone had been inside this transmission before, so it is possible some parts were subbed from an earlier box. Are the bearings supposed to be interchangeable? That is what I understood from Larry and Sam's document on VTR..

 

[JerryVV]

I would suggest that they are not interchangeable as the countershafts would be matched to the bearing style originally installed. When you say loose ones are they each individual rollers or are they captured in a cage but the OD is exposed and runs on the ID of the countershaft? Is there still a solid cage in the countershaft that needs removed? If no cage still in the countershaft then it looks like you have the latest style bearings that were installed in the TR6 and maybe the 250 boxes. And if what you were exchanged by Moss are captured but the OD is exposed then you have the correct bearings. Maybe photos would help.

 

[DanB]

What came out are the caged bearings, with needles exposed on the outside and inside of the cage. The first bearings I bought were shell bearings, with needles only exposed on the inside. The shell would not slide into the counter gear, but may have gone if pressed or driven in. I didn't think that could be right, for fear of damaging the bearing. What I have now are loose needles. Apparently this method was used on early transmissions, and 24 needles are glued in place with grease until the countershaft can go in and hold them. I have talked to Moss and am waiting on them to call me back. Meanwhile, Larry Young pointed me to the explanation of the bearings in his document. It looks like maybe I could have used the shell bearings by pressing them in.

 

[JerryVV]

I agree that the shelled bearings may well have worked but do not use the individual bearings, those are wrong for your application.