tranny leak

I'm assuming this is a 727 tranny? More than likely the fluid is coming from the O-ring seal on the tranny dipstick tube(R/H side), the gear shift selector/throttle control shaft seals(L/H side) or maybe the torque convertor seal. These are especially troublesome just after the vehicle is parked and the fluid drains back into the pan.

I have also seen them leak around the reverse switch.
william

They can be tough to get totally dry. What I did was to use some blue rtv silicone rubber and ran a thin bead on both sides of the pan gasket. Before mating the pan to the siliconed gasket you should make sure the pan is cleaned very well with acetone or lacquer thinner so that the silicone adheres to the metal. Same with the tranny side, clean it real good with acetone or lacquer thinner. In addition smear some blue rtv silicone rubber on the bolt threads before you turn them in. Tighten to spec. If you overtighten you can split the gasket.

Having said all that, another place you can have a leak is where the tail shaft joins the main body of the tranny. This will also require a gasket replacement.

I'd try what the other folks suggested before using the last resort of the rtv silicone rubber.

Mac

p-wagon79 said:

my power wagon has a leaky transmission pan. i've replaced it, changed the gaskets, re-surfaced the mating surfaces, but the thing still leaks....how can i stop this from happening?

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I'd bet its one of the seals other than the pan. They all will drip down and make it look like its the pan when its really not.

i don't know.....it is a 727 tranny by the way, possibly has more leaks than one? But unlikely since it's a new tranny with only about 850 miles on it?? don't know

Dis you replace the tranny after it was rebuilt? Does the tranny seem to loose the same amount of fluid each time?

i'm not really sure, i bought the truck with the new tranny already installed, but i don't think it even had a problem leaking before.

Well the best thing I can think of right now would be to clean off the outside of the tranny real good with something like brake cleaner and then watch again to see if you can trace the leak. you can take some small pieces of white rags and locate them near some of the problem areas that i mentioned before abd see if they turn pink. I always torque my pan bolts to the lower end of the torque specs to reduce gasket damage.