There is no converter in the old dual range hydramatic.
It is called a fluid coupling, they do not amplify the torque, like a torque converter, they are missing the stator that a torque converter has. There is no lockup clutch in the fluid coupling. Direct is accomplished by a separate splined shaft.
First like mentioned the idle speed is way too slow, I would think it should be 400 to 500 in gear. The clutch for direct could be binding too ? I'd have to study things more.

Kicking self for selling off my Taskforce trucks.
Still looking for an LCF or conventional big bolt in decent shape.


As of 10-26-2022, A 55.2 Taskforce long bed now the work begins