Leaking Speedometer Gear Housing (Part 2 of 2)
I counted the number of teeth on the driven gear for reference; 40 teeth. The numbers on the housing indicate it is for a driven gear with 40, 41, 42 or 43 teeth (1st pic below). I took a look inside the housing so I knew what I had to deal with parts-wise and then put it back in. It goes in easy, too, the gears engage with no effort. Just make sure the O-ring surface on the transmission is clean. Then I drove around a little so I could verify the leak without all the crud obscuring things (2nd pic below).
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I only needed two parts, the outer O-ring seal and the inner gear shaft seal. I assumed the gear was good. If I still had a leak after a new seal, I'd get a new gear. I tried getting parts at O’Reilly’s but ended up with wrong parts so I found a specialty vendor online to order them from. When the parts arrived, I removed the housing again and installed the new seals. The gear seal is held in by a spring retainer that is held in place by the spring force only, the bore is smooth. The seal is all rubber, no metal ring. The O-ring is straightforward. So everything is easy to remove and replace, just be careful not to scratch the aluminum surfaces.
Old seals
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................New seals
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O-ring....$..1.50
Gear seal...1.50
Shipping....
7.00
Total......$.10.00
(from PATC Transmissions
http://www.transmissioncenter.net/sp...____va.htm#400 )
I replaced the housing, filled the transmission and drove around a little. A few days later, so far so good; no red puddles on the ground like before.
I cleaned up around the pan and external devices on the transmission where leaks usually occur and I am watching for additional leaks.