Oil Quantity for fluid drive coupler 1952 chrysler

Trying to find out the quantity of 10-W oil for the fluid drive coupler on a 52 saratoga. The coupler is isolated, no sump and no engine oil feed. Factory manual only lists oil quantity for a sump shared torque coupler for 10 1/2 quarts. No data for the fluid drive coupler only. 7 quarts fills it full but it needs a certain amount of slippage so that the carb unloader isn't always dumping and the slip allows for the best power output from the engine. Have been trying to get this info for years writing and calling all over the country. Not enough " old timers " left to remember the exact measurement.

You fill it full assembled to the engine. Access is through the floor on the right side of the transmission tunnel hump. You probably already know this but just want the exact quanity spec. I have never seen one.

I don't know the exact amount but it is not critical. As c49er pointed out, the fill hole accessed thru the floor boards, is positioned so that when you fill it up, it will have the correct air space for proper functioning.

As the Fluid Drive is a sealed unit, there must be some air space to allow for heat expansion.

The Fluid Drive will continue to work when half full. In fact this was an early "speed secret". By draining off half the oil you had the equivalent of a high stall speed torque converter which improved acceleration at the expense of gas mileage.

The literature I have seen from Chrysler does not recommend ever changing the Fluid Drive oil, just topping it up annually. Maybe this is why they never mention how much oil it takes.

A lot of us use TDH tractor oil, ISO 22 or ISO 32 grade. TDH stands for Transmission, Differential and Hydraulic oil. It is supposed to be good for the transmission as well as the Fluid Drive.