How do I drain all the transmission fluid out of transmission and torque converter in a 2007 Silverado 1500

Unfortunately, there is no plug to pull for the torque converter or the transmission pan. All you can do is drop the transmission pan, change the filter and replace the transmission fluid. Never get a transmission flushed as it will cause problems. So it would take around 4 to 5 quarts of fluid to refill. There is a procedure my trany guy does to flush the transmission without using any pressure if you like to know how. But it requires a lot of fluid to do this.

The transmission hose that connects to the ac condenser on my 2015 gmc sierra 4x4 was loose and it fell off while driving. Luckily, i was a few hundred feet away from my house when the truck started acting up and as i went to my nearest oreilly store to buy more transmission fluid, i saw the leak start not too far away from where i stopped. My question. Because of the big leak, will my transmission be damaged?

My 2015 silverado, basically same truck, just leaked all its transmission fluid also.

Now would be a good time to replace the trans filter. Drain and drop the pan and change the filter. Take notice if there is a lot of clutch material in the pan. Reinstall the pan. Fix the leak and fill the trans to proper level with the engine running and the trans in Neutral or Park (preferred). After the trans is filled, put your foot on the brake and use the shift lever to select all the gears. Let it stay in each gear for about 15 seconds. Put it back in Park and check the level again. When the level is correct, Go through the gear selections again and notice whether the vehicle feels like the engine wants to pull it. DO NOT POWER BRAKE IT! Drive it around the block and notice if it goes through all the gears as it is supposed to. Stop and make sure that reverse also works. If it works, then drive it. If there was a lot of clutch material on the bottom of the pan, then you might be looking at a rebuild soon. If no material was there, then there was no damage to the trans.