1957 - Transmission noise/issues after fluid drain & refill
 

I drained and dropped the pan on the Chieftain renewed the gasket, and refilled with ATF. Now she does not like to up shift out of first and there is an odd rattle/knock at the front upper quadrant of the bell housing.

Car/trans has 34k miles. Only reason for the service was the leaking pan gasket.

What'd I mess up?

Did you ever find the solution to this problem?

You didn't mess anything up. Your torus cover may have broken. It is a common issue in these transmissions.

There's an o-ring on the transmission pickup tube for the filter on dual coupling transmissions. If the filter was removed and disturbed this old crusty o-ring, it could have lost its sealing properties causing a fluid starvation issue. Very cheap and simple fix

https://youtu.be/nvLshdrFoWc?t=1579

If that O ring was damaged, the car would not move.

The o-ring could be partially damaged and have enough line pressure to get the car moving but not enough for proper operation. It's worth a try.

Apparently you have never rebuilt one of these transmissions.
It doesn't work that way.
A gauge connected to the line pressure tap will confirm what the line pressure is and if you have line rise when you stab the throttle.
I just rebuilt a 56 Cadillac transmission with a defective pump and it had 35 PSI of line and shifted fine.

I'm always a fan of checking the easy/cheap areas first since most problems generally stem from that arena. Seems like horrific odds that the torus cover cracked immediately after a fluid change. Not saying it's impossible but....

Never rebuilt one of these transmissions but watched the one in my 1959 Pontiac torn down and rebuilt by an old guy back in 2009 who went to school at Hydramatc in 1958. I asked a lot of questions during the process. He was a walking encyclopedia about these transmissions.

I have been rebuilding them since the early 80s and I run a shop that specializes in vintage transmissions. The cover is a common failure and the dampener springs in the main bowl are known to break.
I am also the POCI Transmission tech Advisor.

Hey Guys - thanks for picking this back up.

I have not resolved this yet, mostly due to a lack of time. I do think I may have over-filled the transmission, and will double check that next time I can get it running (see other thread on fuel filter bowl gasket blues). Would this cause an issue? The mechanical rattling up front seems to indicate otherwise.

Steve - How can I confirm the torus cover condition? Is R&R the only way?

The car goes into gear (R & D) no problem, but does not shift properly in Low range, but high range it behaves differently.

Jim, a defective coupling cover will case a no 2nd or 4th condition and the transmission will make 1 upshift.
I am supposed to be in the Delaware Water Gap in 2 weeks if that helps.
Overfilling will not cause anything but foaming and venting.

You cant over fill them..

Did you drain the coupling?

Please explain that statement.

The fluid will come out the vent if over filled with too much fluid or if not started to fill the coupling halfway through the filling process on a fresh transmission. That coupling holds a lot of fluid.. Unless the 57 unit is different from the 315 64 unit.. I only know the 62-64 units..

While I have you check out this post.. I wonder how they sped up the filling and draining of the secondary coupling? Wow would that change the personality of that transmission.. I played with changing the valve springs in that box but it was just too hard. So I totally ruined that cars personality by swapping a generic 455/Turbo 400 into it, what a mistake that was!! I should of just left the 389/Super hydro alone!! All it needed was a nice set of 3.08s


The post,

"315 Controlled Coupling Hydramatic"

Super Hydramatic the capacity is 18 pts.

I have never seen a controlled coupling puke because the secondary dumped to fast. The factory says draining and refilling of the S coupling happens in four tenths of a second and for racing we used to modify that by half.

I have seen the dip stick blow out of controlled coupling P 315 , "D" type single and dual range Hydramatic, Turbo 350 & 400 Hydramatic's because they were overfilled and have seen a T-400 with a problem similar because the vent tube was blocked".

Don

Steve, I'll reach out directly. If I can't diagnose further I may limp over to Shawnee and take you for a test ride.

I did not. Fluid was pristine, as it has been leaking and re-filled for the last few years. :D

I just drained the pan so I could R&R the gasket.

I have seen them between a pint and a qt over and not vent.
I have seen them push fluid out of the filler tube if it doesn't have the ball at the end of it.

I may not be there until Thursday