Shift Shaft Seal replace

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BigBlockMopar28

BigBlockMopar28

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'87 truck 727, shift shaft seal is leaking, mainly when sitting. How big of a job is this, and does anyone have any tips to go by here? Is my daily driver, hoping to be able to get this done in a day or 2 assuming no suprises (we all know how that is lol). I'll add that i'm a complete noob to transmissions. TIA fabo!
 
Really easy take the levers off then pry the inner and outer seals out, use a socket and tap in the new ones. Might want to do the dipstick seal also really easy also it is just a o ring on the tube.
 
halifaxhops said:
Really easy take the levers off then pry the inner and outer seals out, use a socket and tap in the new ones. Might want to do the dipstick seal also really easy also it is just a o ring on the tube.
Click to expand...
Yep I got the dipstick seal and the throttle lever seal just incase. Would it be better to do this from inside the pan? Got the pan gasket/filter/fluid for the fluid change anyways.
 
Easier from the top the levers need to come off the shafts. Look at the factory service manual, seriously easy.
 
doing it in car /truck.
I just drop the valve body.
use a couple of body washers ( bolt and nut)
to pull the seal into the case.
 
BigBlockMopar28 said:
'87 truck 727, shift shaft seal is leaking, mainly when sitting. How big of a job is this, and does anyone have any tips to go by here? Is my daily driver, hoping to be able to get this done in a day or 2 assuming no suprises (we all know how that is lol). I'll add that i'm a complete noob to transmissions. TIA fabo!
Click to expand...

There are some good suggestions so far, and the way I do them is to pull the valve body because it makes it so much easier.
For the beginner who has never done one before I would highly recommend the seal extractor/installer tool.
If you happen to scrape up the seal contact area by prying the seal out, you are fairly screwed.
It's pretty much fool proof and I would say can be done in an hour or so.

Chrysler Shift Lever Seal Remover & Installer 1960-2002 LIKE T-1031-A / KD-2392 | eBay

$_58.jpg
 
There's a shaft in a shaft there so there's a outer typical shaft seal and another O ring type seal inside. It aint easy to tell which is leaking but we know which has seen the most movement. I would replace both.
When you drop the pan you'll discover a whole bunch of bolts in that valve body. Most of them are shorter and holding the valve body together. A few longer bolts are holding the valve body and filter in place. A service manual would show the few you need to remove.
I did all this to my 67 904,,, and the front seal start leaking about 3 months later. Stands to reason since they are all the same age. Better luck with yours.
 
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RedFish said:
There's a shaft in a shaft there so there's a outer typical shaft seal and another O ring type seal inside. It aint easy to tell which is leaking but we know which has seen the most movement. I would replace both.
When you drop the pan you'll discover a whole bunch of bolts in that valve body. Most of them are shorter and holding the valve body together. A few are longer bolts are holding the valve body and filter in place. A service manual would show the few you need to remove.
I did all this to my 67 904,,, and the front seal start leaking about 3 months later. Stands to reason since they are all the same age. Better luck with yours.
Click to expand...

All the 7/16 bolts front and rear of the valve body and the 7/16 bolts around the accumulator drops the valve body.
The filters are usually 3 screws and don't need to come out necessarily, unless you just want to change the filter while in there.
 
I did it on 70 dart with a 904. Drop the trans crossmember down, lower the trans a couple inches, remove both shift levers, remove the tiny e-clip from the kick down shaft and be careful not to let the shaft drop down! Not a big deal but if it does drop, you'll most likely have to pull the pan to retrieve it. Get a small pick and pop the old O ring style seal out and slide the new one in. Reinstall the washer and e-clip. The shift shaft seal is a pain to pop out with out gouging anything but it'll come out. Once out you can slide the new one into place and use a socket to push it in. I used a big C clamp on the top of the socket and bottom of the trans to press it in. Reinstall the shift levers and reinstall the transmission crossmember.
 
What happens is that when your car sits the converter drains back. The seal(s) on the shift lever shaft are not sealing and you have a leak.. Been through this, drop the pan, the valve body and replace the seal. Some guys change it with the valve body in but it takes little to drop and then you can see exactly what you're doing. If your pan has a drain plug the job becomes much easier - cleaner...
 
halifaxhops said:
Really easy take the levers off then pry the inner and outer seals out, use a socket and tap in the new ones. Might want to do the dipstick seal also really easy also it is just a o ring on the tube.
Click to expand...

Thanks for info - I will be doing this next weekend trans fluid is to expensive and keeps driveway nasty.
 
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