727 transmission leak

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bbmopars

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i have leak comin below pan,where the neutral safety switch is.It doesn't look like it leakin form neutral safety tho.cleaned area with brake cleaner to see were leak is comin form.when the car isn't runinn.i have changed pans,upgraded to the mopar performance gasket and still leaks in that area. any suggestions why?
 
i have leak comin below pan,where the neutral safety switch is.It doesn't look like it leakin form neutral safety tho.cleaned area with brake cleaner to see were leak is comin form.when the car isn't runinn.i have changed pans,upgraded to the mopar performance gasket and still leaks in that area. any suggestions why?
The shifter kickdown seal is common to go out..
 
i have leak comin below pan,where the neutral safety switch is.It doesn't look like it leakin form neutral safety tho.cleaned area with brake cleaner to see were leak is comin form.when the car isn't runinn.i have changed pans,upgraded to the mopar performance gasket and still leaks in that area. any suggestions why?

The safety switch can leak between the metal section and the crimped on part.
There is a pin in the back of the main case between the main case and extension housing on the drivers side (barely visible and partially covered by the extension housing)
And the little bearing clip ring access cover under the trans mount.
Any of these can look like a safety switch leak at first glance.
 
BBMopars,

In addition to the shifter pivot seal, you may want to eyeball the speedo housing and cooler line fittings. I had all of them, plus the dip stick seal, leaking and seeping on my 727 when I 1st got it. Keep us posted man.

Pat
 
I'm chasing one in mine as well. Like others have said you have to clean it drive it put back in the air. Lots of seals it can be coming from. Speedo, shift seal. Dipstick, pan.
 
I have Torqueflites come in for my $400 rebuild even tho they're shifting fine; just because they're leaking and they're tired of trying to find the leak. I replace every single seal and make sure there are absolutely no leaks whatsoever. I even have them bring the dipstick tube so I can install it myself. I don't want somebody jamming the tube in and nicking the o-ring. And they have to bring in the converter too; so I can check that to make sure it isn't worn or cracked.
 
Speedo, shift seal. Dipstick, pan.

Since I picked up mine in July I've replaced the speedo seal, the pan gasket, the selector shaft seal, the kickdown seal and the extension housing cover seal.

Speedo seal is a snap, bought the kit off ebay. Just pay attention to the dial marks when you reinstall.

The ext housing seal I couldn't source so I used gasket maker. Its tell-tale drip is off the tip of the bolt on the bottom of the crossmember. The rubber inside the cross member will likely be sopping wet from fluid.

For the selector shaft seal and kickdown seal I slid a bottle jack under the tailshaft and pulled the cross member. Lowering the trans slowly I could get to the top where the shift shaft protrudes from the trans case in order to clean all the oily grime off and disconnect the linkages. I replaced the seal by dropping the valve body as had been previously suggested, rather than invest $30 in a tool that may or may not work (or you may or may not have the clearance to make work). I didn't pull the valve body out entirely, just spun it slightly out of the way and zip tied it off to the pan bolt holes to support it. Once I had some clearance I could drive the seal out from the bottom. FYI the kickdown seal is on top of the shift shaft, retained by an e-clip and washer.

Selector shaft seal Napa part #: ATP 13308
Kickdown grommet/seal Napa part#: ATP 14582

Interestingly, the area around the dipstick tube has stayed dry this whole time (knock on wood).
 
Check the kickdown band locknut/adjuster and case threads. It can also leak there. Mine does, I'm thinking Teflon tape on the adjuster bolt which one might be able to screw it out enough to wrap without dropping the pan if it doesn't disengage from the band tangs.
 
Pro tip on finding tranny leaks. I clean the entire outside of the trans with brake kleen (or something similar) and tear a paper towel into little pieces and stuff them all around. As previously noted, some leaks start in one area and run around the pan rail causing you to believe the leak originated elsewhere. The little tufts of paper towel wick up the fluid and show you precisely where the leak is. Bear in mind there may be more than one.
 
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