T Case front output shaft lip seal

redrad · Post by **redrad** » Thu Jul 08, 2021 3:34 pm

Anyone know a reason to install felt before lip seal? That is how I discovered the orientation as I removed the badly leaking lip seal. The manual shows lip seal then felt, but as we all know sometimes things are installed differently
For a reason, just checking before I reinstall by the book.

1951 M38

Post by **jake138** » Tue Jul 13, 2021 12:54 pm

I've moved your question to the Technical Knowledge Base.

Page 198 of the ORD 9 SNL G-740 shows the gasket being installed first, then the lip seal on the outside closest to yoke assembly. In the part description, I don't see a mention of the front seal being felt though, only the rear output shaft is mentioned to have a felt seal.

Front:

7373157 GASKET, front bearing cap oil seal
500068 SEAL, oil, type ML, 1 9/16 x 2.506 x x (output shaft front)

Rear:

7373157 GASKET, front bearing cap oil seal
8331793 SEAL, felt
0500068 SEAL, oil, type ML, 1 9/16 x 2.504 x 1/2

Interesting that their own seal part numbers match between the front and rear, with slightly different descriptions. I wonder now if the felt should not be in the front?

Checking Rick Stivers rebuild guide, he states to install the "main seal" first, and then the felt goes in between the main seal and the yoke, steps A31 and A32 in the Dana 18 rebuild guide.

Now that your post is in the correct spot, I would wait for some seasoned rebuilders to chime in.

Post by **jake138** » Tue Jul 13, 2021 5:52 pm

My curiosity got the best of me and I had to do a search of the forums here.

http://willysmjeeps.com/v2/modules.php? ... nsfer+felt

You'll find quite a few topics where the felt seal is discussed, with a seemingly equal amount of people who did or did not have a felt seal when they replaced their lip seals. Its existence seems to disappear during a change over from a later design.

Install the lip seal, then the oil the felt and install it behind the yoke. If you check a few of the posts in the search linked above, you'll see that some people had a hard time turning their yoke by hand after the felt was installed, and you may need to trim the thickness of the felt if this happens to you.

Good luck!

redrad · Post by **redrad** » Wed Jul 14, 2021 8:29 pm

I went to the Novak website and it shows felt after the lip seal, so I installed it like it was depicted on their parts diagram and happy to report no leaks.
As always good info on this forum.