Re: IT

Posted by Chiefdan On 2023/1/13 19:25:24

"Also can you tell us more about replacing the pinion seal? I have to do that sometime." Pinion seal on Ultramatic equipped 1951 Packard: First remove the lower drain plug on the rear axle and drain old fluid. Next there are two roughly U shaped clips inboard of the outer part of the U-joint. One leg is peened over so you straighten that little leg and pull the clip(s) out with a screwdriver. This lets the bearing caps come out and then the U-joint can be manipulated out and driveshaft dropped. Put a short 2x4 under the driveshaft at the frame X to keep it up out of the way.
Now the fun part. I used a sharp center punch to mark the pinion yoke, the nut and the shaft all in a row for use when re-installing. After trying various bars with extensions, I gave up and used a 1/2" impact at 120#. Still nothing. Tried penetrating oil and some heat from a propane torch on the nut. This seemed to do the trick and the nut loosened. I had already counted the threads showing (2) on the shaft but I also counted the turns to remove the nut. (9+). That is when it got fun. The seal is cone shaped to the outside so there is very little room to get anything between the shaft and the seal. I tried drilling and screws but couldn't move the seal at all. Finally out of desperation I cut the protruding part of the seal out with a small air rotary cut off tool. That gave me room to put a screwdriver with a bend at the tip between the seal and the bearing and pry the seal out.
By then I had had enough fun and cleaned up and quit for the day.
The next day, with a little blue RTV around the outside the new seal tapped in with no trouble. ( I soaked the seal in oil for several days first ). Oiled the pinion shaft and slid the yoke on so my marks lined up and it went into the same spline as before. Put the nut on and tightened it with the 1 1/4" socket as tight as possible with a breaker bar and went back to the impact for the final 1/4 turn. The impact ran out of steam at about where my marks on the nut and shaft were in line so that was it. My U clips were a little out of shape so I straightened them in the vice until they fit the U-joint bearing caps correctly. The bearing caps have a screwdriver slot on the outer cover and this slot has to be parallel to the way the clips tap in for the clips to follow their intended path. Put the drive shaft back in and tapped the clips in with a ball peen hammer and bent over the one leg that sticks out. Re-install the lower drain plug and refill with fluid thru upper plug hole. I used 85-90 lube. This took me two afternoons but I am sure I could do It much faster the second time but I am sincerely hoping there will be no next time. Best of luck with your project, I hope this amateur tutorial helps. Dan