1996 Chevy Tahoe

I had the tramission of my Tahoe rebuilt about 6 years ago when my truck had about 190000 miles on it. When we got it back, shifting would be clunky, but it seemed to work. I was unable to take it back to the original shop because we relocated to a new state. About 3 years after the rebuild, the transmission started not wanting to shift after the car warmed up. It also started leaking fluid. I took it to a different transmission shop, and they told me it needed another rebuild! I thought this shop was attempting to talk me into expensive and unnecessary repairs (they also told me my catalytic converter was faulty and the entire exhaust system needed to be replaced to truly fix the transmission issue). The price of all this was quite high so I parked the truck, and it sat for 2 years.

We again relocated out of state, but I had the truck serviced at a third shop for the move. This shop told me the transmission did not need a rebuild, but it needed to be flushed and conditioned. We did this, and the truck seemed to drive and behave well. It no longer seemed to leak fluid until about a month ago when I added a/2 a quart of transmission fluid because the level was low. I noticed the truck had leaked fluid overnight. This seemed to stop after awhile, but last night, I went into my garage and found that the truck has dumped all of its transmission fluid suddenly. It has not been driven for 2 weeks. HELP!