T221 Rockwell Transfercase

[1969 GMC]

My GMC came with a T221 behind the SM465...now it has a NP205. It did a good job for me for about 11k or so miles, or a year as my DD. Then the front and rear seals both took a crap at the same time, which I still dont understand. I had to check the oil level every day, as it would leak alot. I didn't have time to pull it, as the truck was my dd and I went to school and work 6 days out of 7. One day I topped it off, left for school, and right as I got there I heard this nasty clanking. Yup, all the gear oil had pissed out of it. After that you could tell I had hurt some of the bearings, as it was even noisier than before (btw, the NP205 is about the same noise wise). It lasted for maybe a week, then on my way home from work (after topping it off yet again, I was carrying 6-7 quarts of gear oil with me at this point, as well as a large piece of cardboard to lay on under the truck), it locked up when I was going 55 mph. Not fun.

I took it out of the truck and took the pto cover off, and there was a few drops of gear oil left in it. The gear oil that was left was silver in color, and about 2/3 of the case's bearing balls were in the bottom. The gears dont look damaged but I have no clue why it locked up. Then I called up Meritor (who makes the parts for Rockwell tcases now, as well as brakes and axles for big trucks) and prices are just hideous compared to the 205. The choice was easy for me.