1940 Desoto Transmission R7? electric kickdown?

[40desoto]

I was wondering if anybody knew more information on how the OD functions on this transmission? Is it an R7 transmission? What is the purpose of the two electrical wires coming out of the solenoid on the side? Kickdown?

Also, if I was to convert to automatic how much work would it be to swap to an early 50's Desoto automatic transmmission?

[1941Rick]

one wire should be for power to operate the sol. the other is part of the kickdown system that gets hooked into the dist. there are lots of diagrams here if you search

[40desoto]

one wire should be for power to operate the sol. the other is part of the kickdown system that gets hooked into the dist. there are lots of diagrams here if you search

Could I bypass all of the electrical on the transmission if I just use the OD manually?

[greg g]

you could power the solenoid from a momentary switch to engage and dis engage the OD. The interupter just grounded the points to kill the engine for a second to put some slack in the drive line while the planetary gear set pulled in. You could mimick that by just releasing the gas on the level and flipping or pushing the switch. You would not have automatic kick down for use in passing or when stopping in traffic, but OD is not ment to be used in heavy traffic anyway.

Had a Volvo wagon that had a similar set up. You just let off the gas, pushed the od button on the shifter and then resumed driving when the OD engaged, It automatically disengaged when the shift lever was moved out of 4th position, so you didn;t need to rember to shift out of OD when slowing down or stopping.