I will say almost 100% sure your tranny is shot. You can try dropping the pan and changing the filter to see if you get some life back.

He mentioned surging, it didn't just stop. If it was a broken shaft, it would be bang and no movement. If it was the t-case, it wouldn't be a clunk, it would be a loud slam and a hard jerk. Almost like hitting a car.

If your problem before involved surging and the RPM's going higher, that was your sign your tranny was going out.
Most likely you ran a tranny low on fluid that didn't have good fluid to start with. Check the color. Should be pink, odds are it is dark brown, maybe with shavings in it.

 

When he descibed his wife having a little trouble for several miles and it dying when she was almost home, that was a pretty good indication that she wiped out the tranny, he should have mentioned that first.

That what happens you have trouble for several miles and just keep driving hoping to just make it home, you destroy stuff.

 

There is a "Quick Fix" for this problem. It is called Craig's List. That is where most Disco's end up anyway. Just put "Cannot be driven as is, must be towed"

Somebody will probably be willing to give you a few hundred for it.

 

So, have you posted it on Craig's List yet?

 

Did you ever crawl under and see if a drive shaft was rotating when in gear?

 

I guess it is gone now.

 

... nevermind ... same issue, transmission pump died.