My 90 240 leaked at the tailshaft seal. Fairly common problem with high mileage automatic 240's. The transmissions are basically the same. 240 uses an AW70, 940 uses an AW71.

Don't know if 940's have tailshaft seal leak issues. Check where the driveshaft attaches to the transmission. That is where you'll see the most fluid but because of the spinning parts it will spray fluid everywhere.

Have you looked at the cooling lines themselves? 240 cooling lines were attached to the frame by a little metal bracket. Over time, the vibrations in the metal would cause the cooling lines to develop a hairline fracture underneath the bracket where it is impossible to see without removing the little bracket. BTDT too...:)