Tranny leak

1994 FORD EXPLORER
250,000 MILES • 6 CYL • 4WD • AUTOMATIC
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RON BALDWIN
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I just bought, it was sitting for almost 4 years, it had only been started now and then. I drove home, while driving no visible leaks anywhere temp gauges were all normal reading. When I got home the tranny started leaking from where it buts up to motor. I am thinking seals are bad for it sat so long and it was not driven. The tranny fluid was coming out pretty fast, the tranny was not hot and it shifted properly the time I was driving it. What would think would be wrong with it? Also there was old gas left in the tank the guy told me he did add more to it, the motor runs strong but was very sluggish but no oil leaks and no major sound coming from motor
Aug 27, 2016 at 1:13 PM
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CARADIODOC
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Main suspect is a front pump seal is leaking. Fluid will run out from the bottom of the bell housing right behind the engine.
Aug 27, 2016 at 1:27 PM
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RON BALDWIN
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I was thinking that myself do to it sitting for so long
Aug 27, 2016 at 2:13 PM
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CARADIODOC
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Actually that shouldn't do it, but with no fluid circulation, rubber seals can dry out. There are seal conditioner additives in oils to keep them pliable, so running the engine even once every few months should be sufficient to keep them wet. I've seen front pump seals suddenly crack from dry-rot and start leaking on vehicles that are being driven daily. What is more concerning to me is the fiber clutch plates drying out when the fluid runs out of the rotating housings. We soak those plates in transmission fluid before installing them during a transmission rebuild. That is so they aren't dry when the transmission first starts spinning. It seems to reason the same damage will occur to them on a vehicle that sits for a long time. That said, I have a '93 Dodge Dynasty with 4,950 miles. It has sat multiple times for more than six years without being started. Drove it well over 100 miles this summer, . . . and no transmission problems.

The time when front pump seals are most likely to leak is after a removed engine or transmission is reinstalled. That seal gets hard and brittle from age, then when the engine and transmission are separated, the full weight of the torque converter drops down on the seal and cracks it. Experienced mechanics will try to stuff a wedge under it to support it, but that rarely works. It's best to just include a new seal in any repair procedure. Once the parts are separated, it just takes a couple of extra minutes to pop it in.

I'm sure sitting has had something to do with this, but blame it more on mileage.
Aug 28, 2016 at 12:46 AM