Trans leak bad.

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plumkrazee70

plumkrazee70

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I replaced the filter And pan gasket on the 904 and put 5 QTS in it and started it in neutral and let it warm up. I continued to add fluid until it showed full on dipstick. I moved it out of the garage (about 20ft) and back again. I went out there a few days later and there was trans fluid everywhere. I checked it out and the only spot I can see it leaking was from where the dipstick tube meets the pan.

I fired it up and the stick was on the add 1 pint mark. I haven't filled it back up yet. I did remove the dipstick tube to see if the o ring was bad and it puked fluid out of that hole. Is that normal with the tube removed?

Was it over filled? Did I install the filter wrong?

Thanks for the help and sorry for the long post.

70 dart 340 auto.
 
I had a problem with my 904. I got a deep pan and I installed a locking dip stick. I did same as you put about 5 quarts in it and fired it off. Then slowly filled it up letting it warm up to the fill line. Well when I was done I shut the car off and let it sit over night. The next day I look under the car and there is a bunch of trans fluid under the car. It took me a while to figure it out. My trans was leaking out of the shift shaft seal because there was too much fluid in it and it was soaking the seal and it was swimming in trans fluid. So I drained about 1.5 quarts out of it and no more leaking. I now put my own mark on the dip stick. It sounds to me like yours is too full also is my guess.
 
Mad Dart said:
I had a problem with my 904. I got a deep pan and I installed a locking dip stick. I did same as you put about 5 quarts in it and fired it off. Then slowly filled it up letting it warm up to the fill line. Well when I was done I shut the car off and let it sit over night. The next day I look under the car and there is a bunch of trans fluid under the car. It took me a while to figure it out. My trans was leaking out of the shift shaft seal because there was too much fluid in it and it was soaking the seal and it was swimming in trans fluid. So I drained about 1.5 quarts out of it and no more leaking. I now put my own mark on the dip stick. It sounds to me like yours is too full also is my guess.
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Interesting. So the long term fix is to replace that seal? How did you know how where to make your mark?
 
plumkrazee70 said:
Interesting. So the long term fix is to replace that seal? How did you know how where to make your mark?
Click to expand...

I didn't replace the seal. Draining the excess fluid to below the seal automatically fixed it. After I drained it I put the mark on the dipstick once I got it warmed up again.

I forgot to mention that I had just rebuilt the complete Trans myself so all the seals etc were new.
 
Mad Dart said:
I didn't replace the seal. Draining the excess fluid to below the seal automatically fixed it. After I drained it I put the mark on the dipstick once I got it warmed up again.

I forgot to mention that I had just rebuilt the complete Trans myself so all the seals etc were new.
Click to expand...

Tonight I will drain some out and see what's up.

What are the characteristics of an over filled trans?
 
plumkrazee70 said:
I'm positive it leaking from where the dipstick tube meets the pan.
Click to expand...

It should never leak from the dipstick tube, so the answer is yes.
The seal needs changed to stop it.
When the car sits after you shut it off some of the fluid in the converter drains back into the trans filling it above the normal level.
This is where a dipstick tube and linkage seals will leak, even though it shows the right level when running.

The amount of drainback is directly related to the pump bushing and pump gears wear, but drainback is normal.

Putting a new lower mark on the dipstick will cause it to be low on fluid all the time.
In Mad dart's case he is probably running his a pint low, which is borderline ok.

A little trick I use is to run it right before I pull the dip stick, speedo gear or driveline as this ensures the converter is full and the fluid level is at it's lowest level in the pan so you don't loose so much.
 
TrailBeast said:
It should never leak from the dipstick tube, so the answer is yes.
The seal needs changed to stop it.
When the car sits after you shut it off some of the fluid in the converter drains back into the trans filling it above the normal level.
This is where a dipstick tube and linkage seals will leak, even though it shows the right level when running.

The amount of drainback is directly related to the pump bushing and pump gears wear, but drainback is normal.


Putting a new lower mark on the dipstick will cause it to be low on fluid all the time.
In Mad dart's case he is probably running his a pint low, which is borderline ok.

A little trick I use is to run it right before I pull the dip stick, speedo gear or driveline as this ensures the converter is full and the fluid level is at it's lowest level in the pan so you don't loose so much.
Click to expand...

Thanks Trailbeast. I was doing more research and found the torque converter drain back valve may be at fault, letting to much fluid back into the pan.

If this indeed the case where is that valve and can it be replaced while trans is in car?

I don't think its the other seal mentioned since the only spot its leaking is on the passenger side from the bottom of dipstick tube. The bell housing is dry.
 
I have a huge cooler at the front of the car. When I first filled it up it took 13 quarts. I still have 11 1/2 quarts of fluid in mine.
My pump gears are new as well as the bushings so in my case I doubt it's drain back from the converter....now draining back from the cooler may be a different story since it sits higher than the Trans.
 
There is an O-ring on the lower part of the dipstick tube, which seals it to the transmission case. You can remove the tube, replace the O-ring, and reinstall it, which will probably solve your leakage issue. Make sure you spray off the area where the tube mates to the transmission with some carb cleaner before you take it apart, so you don't get any crud in the transmission, and lube up the new O-ring real good.
 
plumkrazee70 said:
Thanks Trailbeast. I was doing more research and found the torque converter drain back valve may be at fault, letting to much fluid back into the pan.

If this indeed the case where is that valve and can it be replaced while trans is in car?

I don't think its the other seal mentioned since the only spot its leaking is on the passenger side from the bottom of dipstick tube. The bell housing is dry.
Click to expand...

I highly doubt that is the problem, as I said it is normal for drainback to happen but the seal on the stick shouldn't leak anyway.
Fix that seal and you will be good to go.

Mad Dart said:
I have a huge cooler at the front of the car. When I first filled it up it took 13 quarts. I still have 11 1/2 quarts of fluid in mine.
My pump gears are new as well as the bushings so in my case I doubt it's drain back from the converter....now draining back from the cooler may be a different story since it sits higher than the Trans.
Click to expand...

Ah, in your case it is the cooler and the converter both.
Even though everything is new they still drain back (just the way it is)
In your case you have two areas of drain back making your non running levels even higher, but your linkage and stick seals don't leak. :)

73Scamp318 said:
There is an O-ring on the lower part of the dipstick tube, which seals it to the transmission case. You can remove the tube, replace the O-ring, and reinstall it, which will probably solve your leakage issue. Make sure you spray off the area where the tube mates to the transmission with some carb cleaner before you take it apart, so you don't get any crud in the transmission, and lube up the new O-ring real good.
Click to expand...

Very good advise.
I always put a little RTV around the inside of the hole right before the tube goes back in so it lubes the oring going in and seals completely.
Most don't, but I HATE wet, or even damp spots. :D
 
TrailBeast said:
I highly doubt that is the problem, as I said it is normal for drainback to happen but the seal on the stick shouldn't leak anyway.
Fix that seal and you will be good to go.


Oh ok I missed understood what seal you were talking about. That was on my list to replace tonight.

One more question if I may, Is the /6 904 dipstick tube the same as the SB 904?

Thanks again for the advice!
Click to expand...
 
plumkrazee70 said:
TrailBeast said:
I highly doubt that is the problem, as I said it is normal for drainback to happen but the seal on the stick shouldn't leak anyway.
Fix that seal and you will be good to go.


Oh ok I missed understood what seal you were talking about. That was on my list to replace tonight.

One more question if I may, Is the /6 904 dipstick tube the same as the SB 904?

Thanks again for the advice!
Click to expand...

Hey, no problem.
Not positive on the dipstick tube, but I think they are the same except for maybe the bracket that bolts to the block.
Depth of the tube and the stick in the trans would be for sure.
Click to expand...
 
I have found that sometimes the mounting bolt on the dipstick tube (at the bell housing) preloads the dipstick and causes the o ring to leak. Make sure the tube sits nicely before torquing the bolt down, and tweak the tube if it doesn't. A little rtv on the o ring is also a good idea.
 
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