Help with TH400 Shift Shaft Seal
05-06-2010, 01:33 PM
#3
Safety Car
Member Since: Jun 2004
Location: Beecher Illinois
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And protect the seal when you slip it on.
I just bought ANOTHER for my white79, was going to piggy back it over the other one. I had replaced that one last fall, still leaked.
Upon close inspection, I could see a sliver of rubber peeking out, I had torn it even with my patience installing it.
Pulled that one out and installed the new one. I coiled up a thin flexible piece of plastic inside the seal and slipped the plastic coil over the shaft and slid the seal on and slipped the coiled plastic off. No leaks after a week
Actually, the plastic coil was made from one of those plastic warning tags affixed to the electrical cord of my wifes hair dryer. Happened to be handy.
I think she knows not to use it in the shower
05-06-2010, 02:15 PM
#5
Team Owner
Put Vasoline on the shaft (and on the edges of the flats) before you install the seal. That will help keep it from getting cut. Work it slowly over the flats on the shaft so that the edges don't slice the seal lip. If you want, you can use some emery cloth or other fine sandpaper to just knock off the sharp edges on those flats. Do not scuff up the shaft journal behind the flats.
05-06-2010, 08:11 PM
#7
Le Mans Master
Another way is to wrap a piece of heavy paper around the shaft to protect the seal as it passes over the flats.
05-06-2010, 08:28 PM
#8
Drifting
Member Since: Jun 2005
Location: grand prairie texas
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A couple of months ago I replaced the shaft seal on my 77 with the turbo 350 transmission and I have a mom & pop transmission place close by me and they just loaned me the removal and insertion tool. I purchased the new seal from A/zone and it looked real cheap and I showed it to that transmission shop and he showed me the seal they use and it was a much better seal and he actually gave the new seal to me also. The problem I had was I could not get the insertion tool lined up straight and I had to remove unbolt my crossmember and lower down the engine and transmission and exhaust system enough to line up the tool. Hopefully yours will be easier. Getting that seal in straight is critical.
