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My ultramatic is fine till I turn the car off. Then the fluid rises and begins to leak out of the two "cross shafts" The lower one ( I think) was an easy repair and has been resealed. the other one however it appears the trans needs to be dropped. Is there anyone in the Detroit area that could do that job? The puddle under the car is a pain. Not to mention replacing the fluid as well. Also a pain. Any suggestions would be most appreciated.

By any chance have you added an external cooler? I added 3 to mine which added a bit of oil capacity. I didn't make an anti drain-back hump in the lines on the way back to the trans. After sitting awhile, it would leak quite a but. I suspect that the trans doesn't do well a quart or two over-full and when sitting off, the fluid that's in coolers higher than the trans drains back, overfilling it. I've had the engine out for a couple years since then, but it's something i was meaning to address when it goes back together.

Just a thought.

no the car is factory stock. At least as far as I can tell. it is just the cross shaft seals are bad and one is a bear to get at. I think the trans has to come out to change it. No way I can do that

I had a similar leak on my '54. The mechanic drilled a hole in the frame to provide access so that he could remove the shaft and replace the seal. Transmission was not removed and the leak was fixed, thankfully.

Les

Les, was that for the upper shaft? I think it was the lower was no problem and has been changed. I will need to look into that. I am unfamiliar with what would need to be done to remove that shaft. With or without a hole in the frame.

I am wondering what you are calling an upper shaft. There is the manual select shaft on the drivers side and the throttle shaft on the passenger side but IIRC, those are both exiting the case at the same level. Which one is leaking or is it coming from higher up.

Likely my mistake as per "upper". But they both were leaking. one we could reseal one not. I assumed it was "Higher up" due to my mechanic saying he would have to drop the pan to get at it. sorry I don't know what IIRC means Brian

Sorry about that. There are 7 or 8 definitions of the abbreviation IIRC and the one I meant in this context was "if I remember correctly".

Some of the Ultra cases have deep enough recesses that if the bore is cleaned of any dirt and grease a new seal can be installed and pushed up next to the old. Many have been able to do this as a quick and dirty fix. If the case is one of those that has a shallow recess or if that procedure has already been done then nothing to do but remove the pan and pull the shaft out to remove the old seal(s). Manual shaft will need a hole in the frame to pull it out without removing the trans but the throttle valve shaft is removed from inside the case.

If you do try a second seal over the first be sure the shaft is clean in the area where the new seal will sit but be careful it is not rough, scratched or gouged or the new seal will fail in short order. Throttle shaft side may still require a hole in the frame in order to get a socket or other tool over the shaft to drive the seal straight into the bore

witch seal can be done with out a hole in the frame or dropping the pan? I am sure the one that we resealed the pan was not dropped. Sorry I don't have a cell phone so I don't text or the like so I know very few of the abbreviations used today

If there is more than one seal on now the old will have to be removed. To remove the old seals without damage to the shaft surfaces it is best to remove the shafts. It may be possible to get some kind of screw into the old seal and pull it out with the shafts in place but that would be quite a feat with the trans in the car.

The selector shaft on the drivers side is about 8" long x 5/8" diameter give or take and once the internal pieces are disconnected the shaft will have to come straight out so needs a hole in the frame.

The throttle shaft on the passenger side is smaller -- maybe 3/8 or so in diameter but due to the lever on the inside end it is removed from inside the case. Passenger side would not need a hole for shaft removal.

The problem is both seals are inserted from outside the case and need to be driven into the bore and seated. In order to do that you would use something like a deep socket that would fit over the shaft but inside the bore as a driver. You can see if there is enough clearance on the throttle side to insert from the bottom and turn it onto the shaft and use something like a pry bar to push the seal in but if not, to insert the socket straight on over the shaft and then drive it you will probably need a hole in the frame on that side so socket length can slide straight over the shaft and then be tapped with a hammer

Here are a couple of photos of a 55 Ultra. Ross or someone who has done the procedure on an older Ultra can confirm for sure but I believe the 51 selector shaft and procedure is the same. The throttle shaft is similar in seal replacement but the shape of the shaft and inside lever a bit different in 51.

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