Ok, here's the hole I've dug for myself with my SM420 conversion. :mad:

Does anyone know if a bearing exists with an inner diameter to fit a 3-speed input shaft, and an outer diameter to fit a 4-speed t-case housing (input shaft location)???

Background: I had hoped to install 3-speed gears in my 4-speed case. However, those who are doing this switch are using the plate style adapter with an SM420, which does not require use of the input shaft bearing (I'm guessing on this, but it sounds right).

However, I'm using an AA adapter with the 10 spline spud shaft. This is gonna require the rear bearing and spacers to keep the shaft located. As I started tearing my 4-speed case apart tonight I found out that the 3-speed and 4-speed bearings are different. :mad: :nuke: :mad: Actually, kinda funny.

Now my choices are: 1) find a bearing to fit my application, or
2) just rebuild the 3-speed case.

I just got Don Amway's t-case bracket, but my 3-speed donor case is a 69 (brittle). I'm kinda worried about this. I'm currently running a 2F, 4.11's, lock right in front, no slip in rear, and 16/35 Boggers.

Should I rebuild the 69 case or cut my losses and find a 70's 3-speed case???

Just bring both bearings to a bearing supply house and have them get you one that has all the right dimensions.

Cory

Found a bearing that should fit. Has the right dimensions, but with a snap ring groove thru the od. Should'nt hurt anything. Comes in tomorrow UPS.

Thanks.

Well, got the bearing (NACHI) and it fits perfect. However, I finished dissassembling the 4-speed t-case and found out it had been previously damaged and rebuilt. Damage is too questionable to trust using it with with the SM420, so know I'm shopping for a new case. Dammm...:mad3: :mad3: