I'm swapping in a cummins with an 47RH into my '78 Ford Crewcab. For the Overdrive, I plan on using a switch to actuate the overdrive and a switch to actuate the TC lockup.

Here's my question. If I'm driving on the freeway and I have the OD switch flipped so the OD is engaged, does the trans automatically shift out of OD if I slow down? Or do I have to flip the switch to OD off?

And what happens if I accidentally leave it in OD and come to a stop?

I know if you leave the TC in lockup and come to a stop the engine bogs down and it shuts the motor down.

 

most likely would stay in overdrive and be impossible to get going again, although i dont know if the drop in line pressure from the pump slowing down would make it come out of overdrive From my experience you may have better luck with replies on dodge related questions if you put the word AIRDOG, YETI or ENERGYDRINK, in your post.

 

Or perhaps if your post had 18 foot wide trailer mirrors on it.....