Part
2 – Servicing Seal on Transmission Output Shaft - LJ20
How to revise the old seal into one with a new sealing surface.
Procedure
by Stevec – Written by Myers
Note: This “How To” outlines Stevec’s procedure for creating a new seal by combining a new seal with the old seal removed from the vehicle. To do this the old seal must be removed from the transmission without damage (see Part 1 – Servicing Seal on Transmission Output Shaft – LJ20)
The original 28X42X22 seal is unique in that it was designed to install over the end of the transmission instead of inside the transmission end as is more common. Because of this, it is necessary to salvage most of the old seal and install a new sealing surface in the form of a new 28X42X8 seal which is installed inside the old seal.
1. Construction and dimensions of of old seal:
A. The old
seal was constructed of a metal ring with a rubber coating which included
rubber lips providing a sealing surface when installed over the output shaft.
2. Modifying the old seal: The old seal is modified by removing its sealing surface. There are two ways this can be done. (A or B)
A. Using band saw, cut-off tool, or other clean cut means to remove the end, including the metal lip from the seal.
B. Using razor knife, Dremel tool w/steel brush, or other means to remove the rubber sealing surface from inside the steel ring leaving the inside of the metal ring clean and a with a clean metal lip.
3.
Pressing
in the new seal:
A. 
With both the old seal
and the new 28X42X8 seal in upside down position, place the new seal on the old
one and press it in all the way down using a shop press or other suitable
means.
B. 
If desired, you can also
apply Loctite Gasket Maker to the front of the new seal prior to pressing it in
and also to the back of the new seal after it is pressed in.
4. Notice:
Apply grease to the new sealing surface before installing it back on the
transmission.