Transmission / Overdrive: DG-250-M locks up when I want it to – not automatically.

[Charlie D]

There was recently a post started by Yatipope covering the shifting of his Flight-o-matic. The forum was very helpful to him. I now want to present a situation with my DG-250-M in my 1955 President State Sedan. The tranny will shift from 1^st to 2^nd smoothly at around 10-15 mph. It will not lockup until I lift my foot off the accelerator pedal. That could be at 30 or 60.

I fretted about this the first year or so I drove it. The longer I have driven it the more it has grown on me. I think the linkage must be really close to being set right. In the Flight-o-matic thread, lengthening the linkage was mentioned as a help with that situation. Harryhawk even posted the length from the bend to the lock nut on his car.

I personally prefer being able to control when the car locks up although now I am in another quandary. My current project, a restomod ’55 coupe, is progressing slowly but surely. When it gets pretty close to being done I plan to run the car through the BAT site. I do not know how potential bidders will feel about “forcing” the lockup vs. the Tranny doing it automatically. Right now I tell people that it is a semi-automatic.

I guess this post hopes to solicit two responses. One, Should I try to get it shifting automatically and any help/suggestions on how to do that. Two, How do you think bidders will react to how it shifts now.

Charlie D.

[StudeRich]

Are you confusing "Shift to High" with Lockup?
There is not, or should not be ANY lockup of the Sprag Unit in 2nd. it happens automatically on the 3rd. (High, direct) shift.

There also should not be any 3rd. Gear Unlocked !

Any performance other than that, could mean the Throttle Pressure still is not adjusted correctly per the Studebaker Automatic Drive Manual.

TOO smooth or early shift could mean Low Oil Pressure, due to throttle adjustment.
A forced downshift should take it to Hydraulic 2nd. Gear, converter unlocked.

[Charlie D]

Rich,
I am talking 3rd gear.

[64V-K7]

Rich,
I am talking 3rd gear.

The gear ratios in a DG250M are 2:31::1 (1st gear) --> 1.43::1 ( second Gear) -----> 1::1 (Converter Lockup, cancelling out torque multiplication) ) there is no 3rd gear, only a 3rd speed

[Charlie D]

Thank you for that explanation.

[StudeRich]

I was only referring to this, appears to be 2nd. because no 3rd. speed mentioned. Quote: "The tranny will shift from 1st to 2nd smoothly at around 10-15 mph. It will not lockup until I lift my foot off the accelerator pedal."