904 tranny

I thought it seemed low myself, but that's what Haynes shows for a 904 tranny.

I have now pulled out my 71 model year Chrysler Service manual and it shows that you start with 6 quarts then you should start the engine and allow to idle for 2 minutes, then shift tranny into all gears ending up in neutral, then recheck fluids and bring fluid level to add one pint. Once the tranny is at normal operating temps, then recheck level and add enough to bring the level to between the full and add one pint mark.

I think I'd trust this over Haynes, since this is from the boys who built her.