I drained my transmission through the underside O/D plug, and now it will only take 1.5 quarts before fluid spills out of the filler hole. I can only conclude that I should've pulled the standard underside plug as well. The unit, transmission and overdrive, must retain lubricant when only one of the two plugs is removed. According to the manual, the correct capacity is slightly over 2 quarts, so I must have retained about .5 quarts. Does this sound correct? Thanks all.