56 Dynaflow Breather leak

[Guest Koala]

I am trying to save some time by asking whether anyone has experienced and fixed a oil leak from the breather on top of the rear extension housing of a 56 Buick Dynaflow. Thought it was the usual torque ball leak but the oil is coming out forward and higher than the ball.

When filled to the proper level while cruising down the highway it will quickly blow out oil until it does not register on the dipstick before it settles down a bit.

I guess that there is supposed to be a short pipe attached to the fitting in the extension housing but this is broken off on my car.

When I changed the trans oil with the front of the car jacked off the ground the last couple of litres of oil added just ran out of the breather until I started the engine.

Any ideas on what I need to fix the leak and if so where I can find the parts??

Koala

[Leif Holmberg]

Can`t help you with your problem but here is a picture of the pipe you are talking about,but this is from a 1954-1955 Dyna Flow.

Leif in Sweden.

[JohnD1956]

before taking anything apart, please post a photo of your transmission dipstick. I wonder if the cap has come loose and the stick is going too far down the tube, resulting in overfill of the transmission?

[Guest Koala]

Thank you for that Lief, yes the tube is missing from mine.

And John, my dipstick has part number 1168320 stamped on it and measures close to 17 inches from the cap to the full mark.

I wonder if there is some sort of deflector inside the extension housing that is missing and now allows the oil to feed out the breather when the car is travelling at high speed. Oil would be thrown off the output shaft and out the breather pipe unless there was something to deflect it.

Thanks again

Koala

[JohnD1956]

I'm sure you have the right dipstick but what has happend to my 56 stick is the cap has come loose on the rod and it will easily ride up over it's intended stop. I have to be careful to hold the cap in place when I check my trans fluid to get the proper level.

As for something missing inside the trans may I ask if it leaked like this before you changed the fluid?

[Guest Koala]

Thank you John,

It has always leaked some oil and it was not until I investigated that I found the breather leak rather than the common torque ball leak. This leads me to wonder how many good torque balls have been replaced when the leak is actually from the breather.

No leak to speak of when using the car around town but at high speed on the highway it blows out and covers my nice chrome bumper and the front of my camper trailer. About 2 litres will blow out in 350 miles.

Koala

[old-tank]

Koala

I had a 55 dynaflow that slobbered from the breather. I soldered a piece of brake line to the upper filler tube just above the junction with the lower tube and then attached to the tube from the breather. A later rebuild did not reveal a reason for the overflow, except that the rear pump was inoperative. After the rebuild it did not leak.

It is not that hard to remove and replace the breather with the transmission out of the car, but in car service...you are on your own.

Willie

[60FlatTop]

John,

It is possible that your brakes are dragging and causing the transmission fluid to boil due to the added load.

I serviced a car once that had the transmission fluid blow out of the fill tube and cover the engine compartment.

Put your car in neutral on a level spot and open the door. You should be able to push the car with one foot. If not something is holden you back.

[60FlatTop]

Just another though along the lines of boiling transmission fluid; You might be experiencing slippage in the torque converter at highway speeds and pulling a trailer. Those are things that would overheat the fluid as well.

My BCA chapter participates in the Rochester New York Lilac Festival Parade. We have found that when the parade stops and goes a lot we run a lot cooler. Lots of opportunities to put the car in park and let the engine fan run faster.

If the parade moves along steady and we creep along with on foot on the brake for an hour, we begin to get some overheating. In this case the transmission fluid seems to be heating the radiator tank AND the fan is running a low idle.

Some alternatives to actual leakage for you anyway.

[Guest Koala]

My car blows out the oil with and without the trailer in tow and the brakes are not dragging. The transmission oil is nice and clean with no discolouration which would likely happen if there was overheating and slippage.

And Willie, it would be nice if you could drop by to help remove the breather with the transmission in the car ) Would be a nice clean job...........beers in the refrigerator should help ):D

I think that I will have a look at the breather and replace the broken pipe, maybe even extend it to the filler tube like you did Willie.

Koala

[old-tank]

More possibilities that I ran across in the 1956 Product Service Bulletins. Probably will not help now, but if you remove and rebuild the tranny it may help keep from repeating the problem.

Willie

[1957buickjim]

Funny, I have had the same issue with my 57 Buick Dynaflow. It will run fine, then trans fluid will be blowing out of the fill tube all over the engine compartment. Quite messy. This was after a rebuild as well. I was informed that because I don't drive the car often (twice a month at best right now) that it could be from an air bubble in the torque converter (i.e, the torque converter fluid drains, leaving an air bubble in it?) that will actually overfill the trans pan and hence fluid will shoot out the only vent, fill tube, until the trans pumps fill the torque converter again.

I think that there may be some credibility to that, but to have that happen, there needs to be a leak path out of the torque converter to atmosphere, which could very well be the fill tube.

[Guest Koala]

Thank you for that Willie, What they describe seems to be exactly the problem that I have.

I have not been able to investigate the problem as yet but will now look into whether the leak is caused by this unplugged hole.

Seems like a nice greasy job for a warm summers afternoon rather than the bleak winters days that we currently have.

Koala

[Livisdad2]

I also have a loose cap on the Dynaflow dipstick.  Is 17 inches up from the full mark the correct location for the cap?  That's on a '56 Special...

Edited December 16, 2017 by Livisdad2 (see edit history)

[Johnny 1931 32 DH6]

I have recently purchased another 57 Buick after getting it home and looking at over I took it for a test drive everything was great over the course of a couple days I put about 20 miles on the car and then out of the blue I pulled into a parking lot and it looked like the high-pressure line had broken on the tranny and there was a small fire under the hood put the fire out no damage had the car towed home cleaned up the mess look the car over extensively over a couple days could not find any evidence of a leak anywhere added about 2 quarts the tranny fluid drove it around the house a couple times then I ventured out a little farther about a block or so brought it back home let it sit overnight check it again no leaks so the next day I drove it a little further went to the carwash left the car running gunked everything down cleaned it wash the car and then proceeded home started up my driveway and felt the transmission bog down a little bit and then all the sudden the car stalled almost and then there was another fire got the fire put out transmission fluid all down my driveway but this time it looks like the fluid is coming out the dip stick tube so I have been looking researching and trying to find what the solution to this is I have two other 57 Buick and I have never experienced this problem any help and advice would be deeply appreciated I'm afraid of the car now the second fire was really scary even though I was able to put it out with no damage the fuel line is right there it wouldn't take much and the car would be a total loss thank you in advance for any help and support