What are the symptoms of a dead AT transmission pump?

I'm looking at an older Ford Explorer on craigslist. The owner claims that they were told that the trans pump is bad. Basically, my question is if the pump goes bad, does the entire transmission go? Is the car totally un-driveable or is it bad for the transmission to drive?

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If the pump is bad the rest of the transmission is likely to be tired too. Repairing it will require a rebuilt transmission.

the worst that will happen is the truck won't move. This could happen at a really bad time. We all know murphy was an optimist.

The work to pull the tranny and throw " just a pump" in would be the same as spinning a roulette wheel.

You need a different tranny.

If pump bad the car/truck won't move. Most times low fluid pressure before the pump goes means the transmission will also have to be rebuilt. So expect it to be rebuilt for about 2,500 bucks