Tranny fluid leak

Big Stu

Big Stu

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Joined
Jun 20, 2008
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193
Just had my trans rebuilt with because I had burned up the od clutch pack assemblies and warped the steels. We put in eagle red clutches and checked everything else, dpc converter is fine, input is fine. I drove the truck home and noticed a little fluid coming from the inspection cover, I figured it was residual fluid and halfway brushed it off. I hooked to my 40' gooseneck and hauled a load of cars to phoenix and then stopped on the way back and fluid was pouring out from the inspections cover...so out it came again two days ago...my tranny guy and I couldn't find any damage to the input seal, the converter hub or the pump which were all my suspects for leaks. We replaced the input seal again and I drove it home and it's leaking out from the inspection cover AGAIN :doh: This is driving me nuts and since I use my truck to transport is really throws a wrench is crap when I cant make money....any ideas on what to be looking for? Could the pump have a hairline crack? Has any one had a similar experience? I should note that the input is a billet bd, but it should still take the same seal, correct? Any help is greatly appreciated. Truck is a 2005 cummins dually 4x4
 
Pony_Kegger said:
Could be the pump gasket leaking too.
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Thats a good point, my tranny guy is saying just to buy a new pump but I dont agree with that thinking, cant just replace everything if we dont know whats wrong to begin with. I know my rebuild kit came with a new pump gasket, I wonder why it would be shot out already?
 
Only three things I can think of that would leak from the front.. Front seal, pump gasket, or pump leaking itself due to crack. (I guess if the converter was cracked for some strange reason it to could crack)

I would be looking for an identical transmission to swap pumps with just for poops and giggles.
 
Red Sleeper said:
Only three things I can think of that would leak from the front.. Front seal, pump gasket, or pump leaking itself due to crack. (I guess if the converter was cracked for some strange reason it to could crack)

I would be looking for an identical transmission to swap pumps with just for poops and giggles.
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Those are the three things Ive come up with as well, converter is a dpc triple disk and It looks ok, guess its time to get a new pump gasket and a pump and see what happens...
 
the pump might have been installed inverse to itself, is the tq convertor hub straight and true?

hows the fluid temp? there is also a expansion point in the front, if the fluid expands it has somewhere to vent
 
Finch said:
the pump might have been installed inverse to itself, is the tq convertor hub straight and true?

hows the fluid temp? there is also a expansion point in the front, if the fluid expands it has somewhere to vent
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The hub was fine from what I could see, usually use amsoil and the fluid never gets above 200 degrees even towing the big trailer...
 
when i did my first service, mine puked out about 1/2 a quart over about a week then stopped. we checked everything, and it was just a little over filled. (DD pan and coolers)

now to ask the dumb question, levels good? convertor fully installed? residual left in the bell housing from install?

best of luck
 
Finch said:
when i did my first service, mine puked out about 1/2 a quart over about a week then stopped. we checked everything, and it was just a little over filled. (DD pan and coolers)

now to ask the dumb question, levels good? convertor fully installed? residual left in the bell housing from install?

best of luck
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Check check and check, I thought originally it was overfilled last time, but it just got progressivly worse, started with a drip and then continued on to the point where it was bathing the whole underside of the truck after a long trip..:doh: Going to tear it down this week sometime and post up what I find...
 
Converter drain back? Check level in am or overnight and see if it's way over the full mark. If so start in neutral to refill the converter. If you remove the factory check valve or it's stuck open this will happen. It pukes it's fluid upon start up makes a real big mess. Just one more thing to check.
 
Pulled the trans again and the pump was wet near the top and dripping down into the inspection cover. Replaced the pump, got the trans fluid up to 150 degrees on my gauge which is all the amsoil will do unless I'm pulling the big trailer, and no leaks so far.....the only thing I can figure is that it had a bad check valve, thanks for everyones help....:Cheer:
 
What RPM is the truck running at going 70 MPH. It should be 1900-2000 range. If it is higher then your convertor is not fully locking in and creating heat and then it pukes fluid out the vent( witch is in the bell housing). We see this a lot, especially pulling trailers. You should feel the convertor lock in shortly after in goes into 4th gear.
 
motorzane said:
What RPM is the truck running at going 70 MPH. It should be 1900-2000 range. If it is higher then your convertor is not fully locking in and creating heat and then it pukes fluid out the vent( witch is in the bell housing). We see this a lot, especially pulling trailers. You should feel the convertor lock in shortly after in goes into 4th gear.
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Doing around 70mph on a flat stretch, its around 1900 rpm.
 
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