939 series transmission oil dump?

[Csm Davis]

Okay has anyone ever seen any transmission pump all of it's fluid out on the ground and then not be able to find where it came out? This just happened to me an I can't believe it, here's what went down cranked the truck, let it idle while I started a different truck got back in truck drove fifty yards to concrete stopped got out to look for air leak saw fair puddle starting pulled off pad to keep mess down, got out to see where leak was coming from and it was flooding ran back to drivers side to shutdown,left truck for few days till had time to get back under it, looked later couldn't find where it was coming from only other 939 I have seen dump all the oil like this had busted case so got pullout transmission ready to replace this one pulled truck to shop got phone call from mechanic to come refill transmission so he can make sure it wasn't a busted line. Fill it and make him put clean pan down to catch 5 gallons of new oil, fire truck up and nothing! No drips no runs no spills, wtf? Run truck for hour, drive to get lunch leave it running, drive home ten miles still nothing what gives?

 

[Monkeyboyarmy]

How about the plug for the reverse light switch? (not that the 939's had a light but it is there) It puts pressure to it only in reverse.

 

[nf6x]

How about the plug for the reverse light switch? (not that the 939's had a light but it is there) It puts pressure to it only in reverse.

Where is that plug located? I'm interested in adding reverse lights to my M923.

 

[Monkeyboyarmy]

Should be one of the two 1/8" pipe plugs on the right side just above the oil pan. I don't know which one id which. I would guess that the front is pump pressure and the rear one is reverse pressure. But it's a guess.

 

[Csm Davis]

Will check that today but it dumped in neutral, will check all the switches on the transmission.

 

[03silverado]

Was it overfilled and simply came out the vent?

 

[Csm Davis]

No dumped all fluid out took five gallons to to refill

 

[03silverado]

What about a line to the cooler? If it has one

 

[M35A2-AZ]

Their is a little oil vent/drain/sampler on the front of the Trans oil cooler.
Make sure it is closed.

 

[Csm Davis]

Guys it did this once and we did nothing to fix it but add more oil and it doesn't even drip. If the manual valve was open it would still be leaking. Can anyone say they have seen a hose leak like an open waterhose and without any adjustment it seal completely back closed? This got me to thinking does anyone know if there is a protective valve that would shut off the cooler in case of a massive leak, ie. Bullet holes?

 

[Monkeyboyarmy]

How about from the fill tube. My first A3 didn't have a dipstick and when I fired it up,it puked a bunch of fluid out. Found out that the breather was plugged. Could it have built up pressure and blew the dipstick out enough to empty the fluid?

 

[TiGWolf]

Is it possible somehow when the engine turned over it was running in reverse direction?? My neighbor use to be an owner operator of a dump truck and he had some weird fluke where it fired off in reverse rotation and pumped the fluid out all over everywhere...

 

[Csm Davis]

No on reverse engine it drove fine as it started to leak I like the pressure buildup but not sure why it wouldn't do it again.