1967 K20 SM420 to Rockwell T-221 Adapter Seals

[Chaparralman1974]

Howdy everyone!

I just thought that I would share this with the gang...

1967 was the first year of the "married" transmission to transfer case setup in the K10 and K20 series 4x4 pickups. It was also the last year of the SM-420. After 1967, the SM-465 came into being. That essentially makes the adapter that mates the SM-420 to the Rockwell T-221 transfer case kind of a unicorn of sorts. The coupler that connects the output shaft of the transmission to the input shaft of the transfer case is also unique to the 1967 model year.

Anyone who has been down this restoration path probably has found that the seals are difficult to come by if not downright impossible. Well, after digging around the inter-webs and YouTube, I have found the seal and it is still in production! It is super hard to come by no doubt, but I wanted to share it all with you in the event you need to source it as well. This is the same seal that is in use in the T-221 transfer case by the way. While there is an alternative seal solution (SKF 17381), it is not of the original opposed double lip design. It is likely a superior seal due to the higher temperature rating, but the opposed lip seal, IMHO, is better for the adapter due to need to keep gear lube in both the transmission and the transfer case.

At any rate, if anyone is looking for it, I found the seal at Point Spring and Driveshaft Company (https://pointspring.com/)

The part number is an Axletech (or Meritor) A1805E447.

I just wanted to share this info with the group.


Clay

[67km1590]

I used two of the SKF seals back to back. Two of them together are very close to the same width as the originals. Anyway thanks for the information.