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Ni

That clutch is what separates the ultramatic from other trans.

When working right no slippage. Like a STD trans mission.

If hh56. Or Ross responds. They can explain it.

The clutch in the convertor is to lockup the convertor so there is no slippage after getting up to speed. The low range is thru a set of gears in the transmission case.
With this version of Ultramatic it does not automatically shift from low to high or vise versa. Normally you put the car in High. It starts out in high range with the convertor supplying the multiplication to get the car moving. After it gets up to speed and the load lessens the clutch in the convertor locks up and eliminates slip thru the convertor.
It isn't really recommended to start these in low and manually shift to high. Low was suppose to be for extreme conditions. Such as a very steep hill or rocking the car between reverse and low when stuck etc....

Team
I am in H and i thought it has 2nd and 3rd.
The car stays in 2nd and never goes into 3rd?
Could it be the Torque converter?
We manualy turn the lever connected to the carburator linkage and no change ?We checked all the valves when we opened up the traanny and they all move freely
Any ideas?
why does the torque converter have a clutch between impellers ?

There is no 3rd gear. Only low, high and the clutch is the convertor locks the convertor at a certain speed so there is no slip in the convertor.

If you have the transmission in high it is going to start out in high and stay in high. The only other "shift" you might feel is when the clutch in the convertor locks up.

ok ,so.....now I think im getting somewhere but still a bit confused.
What is the purpose of the linkage from the carb to the lever in the tranny that has control of ,what i thought was a valve lever in the tranny.
I know that the feeling is im at high RPMs ,and in the other ultramatics i have always felt a shift going onto the freeway to a higher gear?

The linkage from carb to the lever on the passenger side is the throttle linkage. Throttle pressure which that linkage controls is one of the most important pressures in the Ultra and is proportional to carb opening and presumably load and to some extent speed. Throttle pressure in conjunction with governor pressure determines when the DD comes in, when kickdown can occur, and also thru other valves how much pressure is sent to the high range clutch assy which affects the clamping force for the clutch plates. Packard tried to have the ultimate in smoothness and with proper throttle pressure pretty much succeeded. If throttle pressure is not correct it will result poorly timed, harsh or damaging operation. Too little throttle and high range clutch pressure is low so slippage and discs can burn, or if too much pressure and the trans will jolt jerk and slam when gears are selected.

Ross gave a method for getting the pressure very close assuming no one has been in and really screwed up the linkage geometry at the carb end.

You can download Studebaker bulletin 340 which is probably the final time anything official was printed on the linkage adjustment procedures for the original Ultra. Instructions start on page 5 of the bulletin.https://www.packardinfo.com/xoops/html/downloads/SC/SB-340.pdf

Howard ,
Thank you ,so what im trying to understand in a basic way.
1.WE only have a high band

SO when I am in Drive or High or normal ,is it the torque converter that actually changes the gear ratio at high end
when i am aproaching 40 or 50?
Im lost a bit on how does it operate as follows is my limited understanding

I start the car from a stop in a high gear low ratio, until I start to reach 50 or 40 MPH and then the Ultramatic changes the gear ratio.
Is the gear ratio changed in the Torque converter or in the transmission.
The sequence of events in my shop is
We changed the Tranny to what we thought was a good tranny ,but used the existing Torque converter because the new tranny torque converter had a leak.The car did the same thing.

In the original Ultras there is no gear shifting whatsoever during normal operation. If you select High range, pressure is directed to the high range clutch pack assy and a piston squeezes the plates together to essentially form a solid unit which is the only connection to the output and rear wheels. Because there is no low mechanical gearing and associated low gear torque, acceleration in high range is best described as very smooth but leisurely.

To start the car moving the torque converter passes engine torque to the high range clutch and the amount of torque does vary. The torque converter at starting out has an effective ratio of I believe around 2.3 and that ratio gradually decreases as the car gains speed. As the ratio starts decreasing and the driving and driven parts in the converter approach the same rotational speed there is more and more efficiency lost in heat and other wasted energy in the converter. To eliminate that inefficiency Packard introduced a clutch mechanism inside the torque converter that when commanded locks the pump stage of the converter directly to the turbine stages and essentially it becomes a locked up solid piece of steel. Along with the solidly locked high range clutch assy the engine power is ultimately transmitted straight thru to the rear wheels just as if the car had a conventional standard transmission that was in third gear.

Throttle pressure sensing the carb opening or load along with governor pressure which senses speed determines when valves move to let fluid pass to the direct drive clutch piston. In normal throttle with a smooth start as Packard assumed their refined drivers would be doing the direct drive comes in at around 20-25 miles per hour. That is the only change that occurs and it is not a shift as such. In a properly functioning unit the sensation when it changes is barely felt with the more common sensation being more of increased quiet level as the engine speed drops and any loss in the converter is eliminated. In older units where the direct drive clutch cork friction material has glazed or hardened there may be a jerk and sometimes a noise which some describe as a mooing sound when the clutch plate finally takes hold.

It will stay in direct drive until the car speed drops to about 11 mph when governor and throttle pressure become low enough the direct drive valve returns to its resting place, direct drive drops out and the car is driven thru the converter again. Up until about 50 mph a sudden push of the accelerator to the floor will cause a forced drop out of the direct drive and back into converter but above 50 and it stays in direct and there is no kickdown possible.

Selecting Low range causes pressure to be directed to the low range band piston instead of the high range clutch. The piston causes a band to clamp around a planetary ring and engine power is now directed thru a planetary gear system and out to the wheels. The torque converter and direct drive works exactly the same except things are geared down in the trans so less speed but more overall torque out thanks to low gear. The car will still go into direct drive but because of the gearing it will happen at a lower speed. Low provides decent acceleration but when its range is topped and the engine is screaming you need to shift to high.

In the original Ultras there is no synchronization between the low band and high range clutch. Many drivers wanting better acceleration started in low to reach a speed then did a manual shift to high. Depending on what was happening at the exact time of the lever movement you could have a period where both band and clutch were applied in which case there was a brief lockup in the trans until the band finally released or a period of free wheeling because the band released before the high range clutch locked. Either situation could cause damage in the trans. The engine could run away and then the high range clutch coming in would abruptly slow it down spinning the clutch plates against each other or with the two gears locked together tremendous force was applied to internal structures. Anyone wanting to do a manual shift is advised not to do it under power but let off the gas for a moment while the shift actually completes before applying power again.

This operation changed in the Gear Start or later Twin Ultra. Packard revised the valving and initiated a second driving range. The original Ultra operation was maintained in one position but they also added a second position for a true Low to High shift and then to Direct Drive transition.

As Ross pointed out there could be worn bushings or shafts. Packard had a valve body with internal passages for the bands but in the fluid paths reaching the converter, direct drive piston and high range clutches they relied on drilled passages in shafts, space between shafts and spaces between meshing gear teeth. All of those paths were directed or separated by bushings or rings riding on or against rotating parts. Wear in one of several places could result in large leaks and preventing the full pressure needed to engage or hold the direct drive clutch piston from reaching it.

There is a pressure port easily accessed on the outside of the trans. You can buy an inexpensive pressure gauge and with fittings and a length of hose measure the pressure going to the clutch. Specs and directions are in the Ultramatic section of the 51-4 service manual if you have printed copy and if not, you can download the Ultramatic section from the Service Manual category accessed from the literature page on this website. There is also a service training manual on the original Ultramatic which gives a lot of theory on operation. For any testing use the SM info for pressures as there were a few changes on Ultras after the training manual was written.https://www.packardinfo.com/xoops/html/downloads/UltramaticTrainingManual.pdf If you measure less pressure than required a worn shaft or bushing is almost a given and will need to be corrected.

Howard, that's as good a description as I can recall ever reading. Great job, you should save it for future use.