Hey guys, my dad has been driving my 87 4runner for some time and says the tranny is leaking from the fill tube (right where the upper and lower filler tube sections meet). He said this only occurs after the engine is shut off. Example: he will start it up, drive around and up and down the street with no leaking occurring. The moment he shuts the engine off the filler tube starts leaking and ends up creating a 4" puddle each time. I know the system has a trans cooler integrated in the radiator. It it possible something is clogged and too much pressure is building up? Or maybe there's some breather valve for the tranny that isn't working? Also note, this isn't the original transmission. I ruined the solenoids on the original and replaced it with the same model tranny from a 93' 4runner about 6 years ago.

 

I spoke with an engineer buddy and he said it's definitely a pressure build up scenario. Is there some way to check the trans temp on these trucks? I don't know if it even has a trans temp sensor? Also, is there a electric pressure relief valve?

 

No pressure relief valve. My '94 (A340H) DOES have a transmission temperature sensor, but I don't know if an '87 is wired for it.

Is it leaking from the bottom of the fill tube? (near the transmission, not at the top where the dip stick cover mates). There is an o-ring there, and it must be there for a reason. http://web.archive.org/web/201408160...39removala.pdf It's a pretty standard part; I'd start by replacing that.

 

The way he describes it no.. it's where the dipstick cover tube mates to the fill tube.

 

How about if it's overfilled?Even if the dipstick shows that the level is at the proper place, how about if the dipstick is the wrong dipstick for that replacement transmission?

 

Good question but why would it just now be overflowing? It's been years since I replaced the tranny and haven't touched the fluid. Just checked the fluid periodically