Thanks Ken C for your detailed response.

It IS the procedure described in the FAQ on this site; the draining of the pan and refill is recommended as the first step. It is NOT the procedure that I have seen recommended in, for example, the IPD hose kit instructions, which recommend only exchanging via the radiator nipple. Maybe the FAQ should be changed in this case?

I was very precise in my measurements, which is why I was stressed out; I didn't want to put any more in, already went above the amount that came out by 1/2 quart in my increasing attempts to prime the pump, so to speak, to get the fluid flowing out again.

I did call a Volvo mechanic, and he recommended, at the stage I was in, with equivalent amounts of fluid in the tranny as what had come out, to forget the flush for now, seal up the system, and try to drive the car to see what would happen.

I did this, and for the first time ever, my engine oil pressure light came on and stayed on. I drove half a block, turned around and came home. For some reason, my engine seems to have dumped its oil! There was a huge spot on my dirt driveway of what appeared to be engine oil (wish I could see it better to make sure it wasn't tranny fluid!).

At this point I'm not going to risk anything; I'm having my very nice 940 towed into a shop, I'm in above my weight class. If anybody has any ideas how the engine oil could have gotten involved with this story, I'd be grateful to know.